layerman: activate meta-beagleboard-extras

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>
layerman: switch meta-ti to angstrom staging branch

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>
layerman: switch meta-oe to angstrom staging branch

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>