update build.gradle to be compatible with the latest android studio
remove software keyboard when switching buffers
before this, the keyboard would stay on-screen but the input field would lose focus, which is pretty useless
i suppose input field should get focused anyway for hardware keyboards?
fix for crash on tab completing using software keyboard
now tab completing is invalidated on input box text changes, which weren't caught by onKey which is only triggered by hardware keyboard events
complete nicknames in last used order
also fixes a couple of other nick completing bugs
this, however, doesn't take into account updateNick
  (see said function in com/ubergeek42/weechat/Buffer.java,
  also the end of com/ubergeek42/weechat/relay/messagehandler/NicklistHandler.java)
 nickname updates should be run on nickname changes and mode changes, but i only see nick additions/removes for this actions, so this works fine in current setup
append “: ”to the completion nick if completing the first word in the input box
Update build files
Merge branch 'master' of git://github.com/oakkitten/weechat-android into oakkitten-master

Conflicts:
	weechat-android/build.gradle
Merge branch 'oakkitten-master'

Closes Pull Request #104
Fix some android lint errors/warnings