Update some comments & error messages

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/scripts/generate_visualc_files.pl b/scripts/generate_visualc_files.pl
index e4092c0..4fad322 100755
--- a/scripts/generate_visualc_files.pl
+++ b/scripts/generate_visualc_files.pl
@@ -1,9 +1,9 @@
 #!/usr/bin/env perl
 
-# Generate main file, individual apps and solution files for MS Visual Studio
-# 2010
+# Generate main file, individual apps and solution files for
+# MS Visual Studio 2013
 #
-# Must be run from mbedTLS root or scripts directory.
+# Must be run from Mbed TLS root or scripts directory.
 # Takes no argument.
 #
 # Copyright The Mbed TLS Contributors
@@ -256,7 +256,7 @@
 sub main {
     if( ! check_dirs() ) {
         chdir '..' or die;
-        check_dirs or die "Must but run from mbedTLS root or scripts dir\n";
+        check_dirs or die "Must be run from Mbed TLS root or scripts dir\n";
     }
 
     # Remove old files to ensure that, for example, project files from deleted