Reduce frame rate reported by framebuffer HAL to 54 Hz

This matches a corresponding kernel change to run the panel at 54 Hz
(allowing us to reduce the pixel clock to allow downscaling of larger
images).

Change-Id: Ib3e6ce2e2ac337fc5dfb2b02ccd31a708decda7b
Add <linux/omapfb.h> header needed for hwcomposer
Enable building of hwcomposer.omap3
Use CM11-specific kernel config

For the moment, we want this for DSSCOMP/hwcomposer support.
Use shrinker when creating final OTA package
Symlink /system/app/{GoogleHome,Hangouts}.apk to /dev/null

GoogleHome is included in some Google apps packages for some reason, but
doesn't fit onto our small /system partition.  Ship a symlink to
/dev/null there, which will cause the OTA installer to write the package
to the bit bucket.  (It's still possible to install the package via the
usual methods -- we just don't want it on /system.)

Do the same with Hangouts, which can be installed from the Market.

Thanks to Ricardo Cerqueira (arcee) for the idea.
Revert "frameworks/base overlay: make the low memory killer less aggressive"

This doesn't appear to be working as intended -- we may need to do some
experimentation to find better values.

This reverts commit 90d022132a354cd7bc09319c04e57ad91f1f19ac.