Added system to build LegacyCamera if specified

Some devices (all 2011 Xperias, and most 2010 legacy devices) cannot use the
default Jellybean camera. Instead they can run the LegacyCamera app
This commit enables using LegacyCamera wrapped into Gallery apk like the
normal JB camera is wrapped into Gallery

To use, just add BOARD_USES_LEGACY_CAMERA := true to your BoardConfig

Credits:
Inspired by a patch by Bryan Gantt <dragonzkiller@gmail.com>
Enhanced by Rashed Abdel-Tawab <rashedabdeltawab@gmail.com>
Thanks for tips and hints from:
	- Konsta Tuomio <konsta09@gmail.com>
	- Arnav Gupta <championswimmer@gmail.com>
	- Ricardo Cerqueira <cyanogenmod@cerqueira.org>

Changelog:
Patch set 1: Fixed up the code
Patch set 2: Use BOARD_USES_LEGACY_CAMERA instead
Patch set 3: Fix up normal Camera stuff
Patch set 4: Clean up. This should be it
Patch set 5: Reomved whitespace, documented the if's and else's, ready to merge now

Change-Id: I2e07032e6a097b8334762af789bf2c72f2515cab