Boot: Use the MCUBoot version of the imgtool.

Uses the MCUBoot version of the imgtool. Adds a Python wrapper script
to work around its altered interface.

Change-Id: I9dc98f254f26de8d379e544a2c59fa6f08d42341
Signed-off-by: Balint Matyi <Balint.Matyi@arm.com>
diff --git a/docs/getting_started/tfm_sw_requirement.rst b/docs/getting_started/tfm_sw_requirement.rst
index a2518d8..9b3e09b 100644
--- a/docs/getting_started/tfm_sw_requirement.rst
+++ b/docs/getting_started/tfm_sw_requirement.rst
@@ -170,11 +170,11 @@
 - CMake (see the "Supported CMake versions" chapter)
 - GNU Make (see the "Supported make versions" chapter)
 - Python3 and the pip package manager (from Python 3.4 it's included)
-- Python3 packages: *cryptography, pyasn1, yaml, jinja2 v2.10, cbor v1.0.0*
+- Python3 packages: *cryptography, pyasn1, yaml, jinja2 v2.10, cbor v1.0.0, click*
 
   .. code-block:: bash
 
-    pip3 install --user cryptography pyasn1 pyyaml jinja2 cbor
+    pip3 install --user cryptography pyasn1 pyyaml jinja2 cbor click
 
 - SRecord v1.58 (for Musca test chip boards)
 
@@ -230,11 +230,11 @@
   installation.
 - Python3 `(native Windows version) <https://www.python.org/downloads/>`__ and
   the pip package manager (from Python 3.4 it's included)
-- Python3 packages: *cryptography, pyasn1, yaml, jinja2 v2.10, cbor v1.0.0*
+- Python3 packages: *cryptography, pyasn1, yaml, jinja2 v2.10, cbor v1.0.0, click*
 
   .. code-block:: bash
 
-    pip3 install --user cryptography pyasn1 pyyaml jinja2 cbor
+    pip3 install --user cryptography pyasn1 pyyaml jinja2 cbor click
 
 - `SRecord v1.63 <https://sourceforge.net/projects/srecord/>`__ (for Musca test
   chip boards)
@@ -492,6 +492,7 @@
    "jinja2",,"Firmware"
    "cryptography",,"Firmware"
    "cbor",,"Firmware"
+   "click",,"Firmware"
    "Doxygen",">1.8","Reference manual"
    "Sphinx",">1.4","User Guide"
    "sphinxcontrib-plantuml",,"User Guide"
@@ -542,11 +543,13 @@
     fw --> yaml
     fw --> jinja2
     fw --> cbor
+    fw --> click
     cryptography --> Python3
     pyasn1 --> Python3
     yaml --> Python3
     jinja2 --> Python3
     cbor --> Python3
+    click --> Python3
 
     [*] --> u_guide
     u_guide --> Sphinx