mm: vmscan: when kswapd is awoken due to reclaim by a running task

Set the priority of kswapd to that of the calling task thus making memory reclaim cpu activity affected by nice level.

http://ck.kolivas.org/patches/3.0/3.9/3.9-ck1/patches/mm-kswapd_inherit_prio-1.patch
Always set noatime no diratime on all partitions! I/O Boost!

Also mod read_ahead to 512. as seems that is faster! in test apps.
Always set noatime no diratime on all partitions! I/O Boost! V2