LatinIME: Add @ character to DE keyboard's more keys

Change-Id: I6a85496e579170a67352160277bfb43125b1e892
Enable gesture typing - (1/3) -LatinIME part

Change-Id: I343b91714144070616d351c5f9fc88a3e50c3e7e
TRDS: Darker Keyboard

Change-Id: I73656060a306774a0996b71ac46f0ba99f0ba68f