Backported ZCache mechanism from Linux Kernel 3.9.11

Conflicts:
	drivers/staging/zcache/Kconfig
	drivers/staging/zcache/tmem.c
	drivers/staging/zcache/tmem.h
	drivers/staging/zcache/zcache-main.c
Adapt ZCache from kernel 3.9 to kernel 3.0
fixes from last commit
Backport Frontswap frontend mechanism from kernel 3.9

Conflicts:
	mm/page_io.c
Backport cleancache from kernel 3.9
Revert "Backport cleancache from kernel 3.9"

This reverts commit dbd1b151f3a4b69e61673a2405b9c41df0a108df.
Revert "Backport Frontswap frontend mechanism from kernel 3.9"

This reverts commit d22df9dd0474cdd463a9b58379bf639b1abc4bad.
Revert "fixes from last commit"

This reverts commit 7e178620dbcbdc2178048b07b5bde4f8638dd578.
Revert "Adapt ZCache from kernel 3.9 to kernel 3.0"

This reverts commit 1db572d3b73be8ee12e1a3f3db2f85534d40ca58.
Revert "Backported ZCache mechanism from Linux Kernel 3.9.11"

This reverts commit 2fcd74624e23def8185668f4821aecf0bf313571.
 1) OC RAM 533MHz

2) tweaked CPU freqs and voltages
3) configs
Improve the performance of memcpy and memmove

Conflicts:
	lib/string.c
fix commit