Add Custom Version

Change-Id: Ie8d17a4607a4e1cb4979d8ac009b582bc169df0a
Settings: Add Advanced reboot option
By DvTonder

This commit adds a setting in Development settings for including options
in the power menu for rebooting into recovery or bootloader, defauled to
off.

When enabled, the Advanced reboot options will only be available once the
device is unlocked.

Change-Id: I692fb732ec1b14ae9a71f2de4b343a05934cdcf9

Conflicts:
	res/values/custom_strings.xml