Moving language switcher to core

Issue: #99 

@jone @phgross In phvs the translation for the live search is done by overwriting the view. https://github.com/4teamwork/opengever.phvs/blob/5c56132cb112545df8cd1894f36c0815e95b8925/opengever/phvs/skins/phvs_resources/livesearch_reply.py
Is there a better way to do this?