Add support for TARGET_USE_CUSTOM_LUN_FILE_PATH

Change-Id: I22507597087eca2cb2b1d364b773fac8256ab43d
Merge branch 'cm-10.1' of git://github.com/CyanogenMod/android_bootable_recovery into devil_touch2

Conflicts:
	extendedcommands.c

Change-Id: I3eb2017e1742f0ad511e70a6fdb67e5b678ac0d3