added crc check for download
updated for papilot testing
Merge remote-tracking branch 'corentin/master' into crc_update

Conflicts:
	src/luftboot.c
Revert "Merge remote-tracking branch 'corentin/master' into crc_update"

This reverts commit 1836fd096b0d6a7f536399dc76837620eafde59d, reversing
changes made to d5527296c35eec68965a8a6f107615d106469b40.
Merge remote-tracking branch 'corentin/master' into crc_update

Conflicts:
	src/luftboot.c (reverted from commit 1836fd096b0d6a7f536399dc76837620eafde59d)
[print] small print change to improve visibility on paparazzi
Merge remote-tracking branch 'molnar/crc_update'