Android ZRAM Optimizations: adapted from Samsung JF series kernel

Signed-off-by: Paul Reioux <reioux@gmail.com>

Conflicts:
	arch/arm/kernel/process.c

Conflicts:
	arch/arm/kernel/process.c
	drivers/staging/android/lowmemorykiller.c
	include/linux/sched.h
	kernel/cgroup.c
	mm/vmscan.c