Don't generate images in .dat format

Change-Id: I7b40ca4d020f7b969d012175845b53b59c68fec4
Build : Copy boot.img to BOOTABLE_IMAGES don't build another boot.img again

Change-Id: Idaa8d4fb40386395cf906b00607f99e762481b11

Conflicts:
	core/Makefile
Build : Allow to use mkimage to append an header to recovery ramdisk (MTK SoC)

Change-Id: I43d90751d695e277760e9338b1d16d63fb8dbbde

Conflicts:
	core/Makefile
Build : Allow to use mkimage to append an header to ramdisk (MTK SoC)

Change-Id: I18edb3e8b91d9c4e8002fd128c7d0e2a2f896b7e
Don't build in blocks by default

Change-Id: I20b117870b1e9a2e7daedb24791cb729366485fa