Make docstring style consistent

Use PEP 257 indented docstring style, mostly: always with """, with the
terminating """ on a separate line if the docstring is more than one
line, and with all lines indented to the opening """.

This commit does not change the text to keep the first paragraph single-line.
diff --git a/tests/scripts/test_psa_constant_names.py b/tests/scripts/test_psa_constant_names.py
index 1f08721..d248ade 100755
--- a/tests/scripts/test_psa_constant_names.py
+++ b/tests/scripts/test_psa_constant_names.py
@@ -1,10 +1,11 @@
 #!/usr/bin/env python3
-'''Test the program psa_constant_names.
+"""Test the program psa_constant_names.
 Gather constant names from header files and test cases. Compile a C program
 to print out their numerical values, feed these numerical values to
 psa_constant_names, and check that the output is the original name.
 Return 0 if all test cases pass, 1 if the output was not always as expected,
-or 1 (with a Python backtrace) if there was an operational error.'''
+or 1 (with a Python backtrace) if there was an operational error.
+"""
 
 import argparse
 import itertools
@@ -25,16 +26,22 @@
 class read_file_lines:
     # Dear Pylint, conventionally, a context manager class name is lowercase.
     # pylint: disable=invalid-name,too-few-public-methods
-    '''Context manager to read a text file line by line.
-with read_file_lines(filename) as lines:
-    for line in lines:
-        process(line)
-is equivalent to
-with open(filename, 'r') as input_file:
-    for line in input_file:
-        process(line)
-except that if process(line) raises an exception, then the read_file_lines
-snippet annotates the exception with the file name and line number.'''
+    """Context manager to read a text file line by line.
+
+    ```
+    with read_file_lines(filename) as lines:
+        for line in lines:
+            process(line)
+    ```
+    is equivalent to
+    ```
+    with open(filename, 'r') as input_file:
+        for line in input_file:
+            process(line)
+    ```
+    except that if process(line) raises an exception, then the read_file_lines
+    snippet annotates the exception with the file name and line number.
+    """
     def __init__(self, filename):
         self.filename = filename
         self.line_number = 'entry'
@@ -53,9 +60,11 @@
                 from exc_value
 
 class Inputs:
-    '''Accumulate information about macros to test.
-This includes macro names as well as information about their arguments
-when applicable.'''
+    """Accumulate information about macros to test.
+    This includes macro names as well as information about their arguments
+    when applicable.
+    """
+
     def __init__(self):
         # Sets of names per type
         self.statuses = set(['PSA_SUCCESS'])
@@ -91,8 +100,9 @@
         }
 
     def gather_arguments(self):
-        '''Populate the list of values for macro arguments.
-Call this after parsing all the inputs.'''
+        """Populate the list of values for macro arguments.
+        Call this after parsing all the inputs.
+        """
         self.arguments_for['hash_alg'] = sorted(self.hash_algorithms)
         self.arguments_for['mac_alg'] = sorted(self.mac_algorithms)
         self.arguments_for['ka_alg'] = sorted(self.ka_algorithms)
@@ -103,14 +113,16 @@
 
     @staticmethod
     def _format_arguments(name, arguments):
-        '''Format a macro call with arguments..'''
+        """Format a macro call with arguments.."""
         return name + '(' + ', '.join(arguments) + ')'
 
     def distribute_arguments(self, name):
-        '''Generate macro calls with each tested argument set.
-If name is a macro without arguments, just yield "name".
-If name is a macro with arguments, yield a series of "name(arg1,...,argN)"
-where each argument takes each possible value at least once.'''
+        """Generate macro calls with each tested argument set.
+        If name is a macro without arguments, just yield "name".
+        If name is a macro with arguments, yield a series of
+        "name(arg1,...,argN)" where each argument takes each possible
+        value at least once.
+        """
         try:
             if name not in self.argspecs:
                 yield name
@@ -160,7 +172,7 @@
                           ])
 
     def parse_header_line(self, line):
-        '''Parse a C header line, looking for "#define PSA_xxx".'''
+        """Parse a C header line, looking for "#define PSA_xxx"."""
         m = re.match(self._header_line_re, line)
         if not m:
             return
@@ -176,13 +188,13 @@
             self.argspecs[name] = self._argument_split(m.group(3))
 
     def parse_header(self, filename):
-        '''Parse a C header file, looking for "#define PSA_xxx".'''
+        """Parse a C header file, looking for "#define PSA_xxx"."""
         with read_file_lines(filename) as lines:
             for line in lines:
                 self.parse_header_line(line)
 
     def add_test_case_line(self, function, argument):
-        '''Parse a test case data line, looking for algorithm metadata tests.'''
+        """Parse a test case data line, looking for algorithm metadata tests."""
         if function.endswith('_algorithm'):
             # As above, ECDH and FFDH algorithms are excluded for now.
             # Support for them will be added in the future.
@@ -207,7 +219,7 @@
     # regex is good enough in practice.
     _test_case_line_re = re.compile(r'(?!depends_on:)(\w+):([^\n :][^:\n]*)')
     def parse_test_cases(self, filename):
-        '''Parse a test case file (*.data), looking for algorithm metadata tests.'''
+        """Parse a test case file (*.data), looking for algorithm metadata tests."""
         with read_file_lines(filename) as lines:
             for line in lines:
                 m = re.match(self._test_case_line_re, line)
@@ -215,7 +227,7 @@
                     self.add_test_case_line(m.group(1), m.group(2))
 
 def gather_inputs(headers, test_suites):
-    '''Read the list of inputs to test psa_constant_names with.'''
+    """Read the list of inputs to test psa_constant_names with."""
     inputs = Inputs()
     for header in headers:
         inputs.parse_header(header)
@@ -225,7 +237,7 @@
     return inputs
 
 def remove_file_if_exists(filename):
-    '''Remove the specified file, ignoring errors.'''
+    """Remove the specified file, ignoring errors."""
     if not filename:
         return
     try:
@@ -234,7 +246,7 @@
         pass
 
 def run_c(options, type_word, names):
-    '''Generate and run a program to print out numerical values for names.'''
+    """Generate and run a program to print out numerical values for names."""
     if type_word == 'status':
         cast_to = 'long'
         printf_format = '%ld'
@@ -282,15 +294,18 @@
 
 NORMALIZE_STRIP_RE = re.compile(r'\s+')
 def normalize(expr):
-    '''Normalize the C expression so as not to care about trivial differences.
-Currently "trivial differences" means whitespace.'''
+    """Normalize the C expression so as not to care about trivial differences.
+    Currently "trivial differences" means whitespace.
+    """
     expr = re.sub(NORMALIZE_STRIP_RE, '', expr, len(expr))
     return expr.strip().split('\n')
 
 def do_test(options, inputs, type_word, names):
-    '''Test psa_constant_names for the specified type.
-Run program on names.
-Use inputs to figure out what arguments to pass to macros that take arguments.'''
+    """Test psa_constant_names for the specified type.
+    Run program on names.
+    Use inputs to figure out what arguments to pass to macros that
+    take arguments.
+    """
     names = sorted(itertools.chain(*map(inputs.distribute_arguments, names)))
     values = run_c(options, type_word, names)
     output = subprocess.check_output([options.program, type_word] + values)
@@ -301,16 +316,17 @@
     return len(names), errors
 
 def report_errors(errors):
-    '''Describe each case where the output is not as expected.'''
+    """Describe each case where the output is not as expected."""
     for type_word, name, value, output in errors:
         print('For {} "{}", got "{}" (value: {})'
               .format(type_word, name, output, value))
 
 def run_tests(options, inputs):
-    '''Run psa_constant_names on all the gathered inputs.
-Return a tuple (count, errors) where count is the total number of inputs
-that were tested and errors is the list of cases where the output was
-not as expected.'''
+    """Run psa_constant_names on all the gathered inputs.
+    Return a tuple (count, errors) where count is the total number of inputs
+    that were tested and errors is the list of cases where the output was
+    not as expected.
+    """
     count = 0
     errors = []
     for type_word, names in [('status', inputs.statuses),