Frameworks Base: Mock SMS (1/4)

This change brings the possibility of simulate the reception of SMS on real devices.
This change includes the setting and security permission.

Ported from http://review.cyanogenmod.org/#/c/23017

Patchset 2: Rebased

Change-Id: I535d5e69fbd9d612f7ed1a635032be7caefeda04
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>

Conflicts:
	core/res/res/values/slim_strings.xml