Cleancache frontend from kernel 3.7
Frontswap from kernel 3.8
Enable Cleancache (and ready Frontswap)

Conflicts:
	arch/arm/configs/gk_tuna_defconfig
Adapt Cleancache & Frontswap on Kernel 3.0

Signed-off-by: Willi Ye <williye97@gmail.com>

Conflicts:
	mm/page_io.c