LatinIME: Add keyHintLabels to all keys in qwerty

This adds a second function to every key. I used the
same second function layout as the keyboard from cm.
We could change this easily if a different layout or
set of keys is desirable.

Change-Id: Ie290c138371b2f9fa082ba7d94a76b30a61428e7
Merge "LatinIME: Add keyHintLabels to all keys in qwerty" into android-4.4