build: Add alternate recovery to pathmap

Change-Id: I2827ace9729b6af8d5b4e637374ccd1e5902dd55
Fix the alternate recovery inclusion logic

Change-Id: Ifb59d61dae44dd639d7f891dc57bb326b06b1118
build: Add script to generate extra images

Change-Id: I53081c7a2b4f18bc8c8a27b04d311a6b078b2022
merge changes from CyanogenMod 10.2 into local branch