The imgtool.py program has been assuming that the input image for
signing has a zero padded place for the header at the beginning of the
image. This is only true for some platforms.
Instead, make this included header space optional. By default, prepend
the header to the image. If `--included-header` is specified to the
sign command, consider the bytes at the beginning of the image to be
padded space for the header. This option is required for Zephyr builds.
Remove most of mynewt specific stuff to a separate port package. This
should make mcuboot less "mynewt'y" and slightly easier to port to.
- Mynewt specific stuff moved to boot/mynewt.
- Sample app moved from apps/boot to boot/mynewt.
- Use MYNEWT_VAL macro only on mynewt port.
- BOOTUTIL_* and MYNEWT_VAL() usage moved to MCUBOOT_ defines.