Added clear() command that shouldn't trigger the callback
Don't build a token for an empty String
Made Lint happy
Removed unused method clear()
Fixed a bug preventing tokens to be added
Updated gradle settings to suppor the latest version of android studio
Made the bestGuess optional (it wasn't being handled properly anyway)
Merge remote-tracking branch 'origin/cardnote' into cardnote

Conflicts:
	library/src/main/java/com/tokenautocomplete/TokenCompleteTextView.java
Creating tokens from unfinished text when EditText loses focus
Merge branch 'cardnote'