Port schedulers from android-msm-mako-3.4-jb-mr2
and adapt N7 Kernel to use them

Change-Id: I30f8145b8cffc500442352ff62edf499c4eb790d
Correctly use PG_readahead

Change-Id: I3e9440e27fd5565fe2841653a334bd167603ab09
Port governors from android-msm-mako-3.4-jb-mr2

Change-Id: I63876b7ba1e5b791789e13a55e4234bc0ad9f99d
Enter some defaults values

Change-Id: Idaff7454f9f4cd61dcb1477edfa09cdfb286be25
Enter some defaults values2

Change-Id: Iae66d9fc67c6b89bc99636121a5351ea2e14e868