This is the start of a python implementation of imgtool. This
implements all of the functionality that was missing in the zep2newt.py
tool, namely creation of keypairs, and converting the public version of
these keys into C code.
Add an --image-version argument to zep2newt.py to allow the major
version number to be set. This helps make testing easier by having
differing version numbers.
These are some simple scripts for signing images (with an example with a
hardcoded path), a fixed root key that matches the one checked into the
code, and a few scripts to use the Segger debugger to flash the images.
David Brown