Launcher3: some tweaks to the default setup

*Throw ROMControl on the front screen
*Replace MMS with Hangouts in the hostseat as it's more current.

Signed-off-by: Andrew Warfield <hiasant@gmail.com>
Change-Id: I9ff665d947d32d94cf4fce62856811c99e08c89b

Conflicts:
	res/xml/default_workspace.xml