galaxysmtd: Kit Kat bring-up

This reverts commit ad3c7b2ba98712c3252cb7b7f40add485e0887be.
This adds samsung stk boolean.
This adds gsm.mk call
This adds omni dependencies (kernel missing on omnirom, just fork)
This adds STK overlay and Custom Hardware Button Mapping
This adds OmniGears overlays for Volume Wake and Hardware Button Mapping

This depends on: https://gerrit.omnirom.org/#/c/2473/
This depends on: https://gerrit.omnirom.org/#/c/2474/

Change-Id: If4ddd8b11a74dd032133ba56891fba2adef446b1