Performance settings [Port CM-10.2]

Includes the following CM-10.2 commits:
http://review.cyanogenmod.org/30667 Performance: BootReceiver: set CPU min/max freqs before CPU governor
http://review.cyanogenmod.org/31886 Adding configurability of frequency cap (min/max) files' path.
http://review.cyanogenmod.org/48007 Cleanup: remove useless checks.
http://review.cyanogenmod.org/51295 Cleanup performance settings strings

Thanks CM.