Moved feedback logic to feedback dialog fragment
Preparing videos for export is now async
Fixed early finish on action mode, added sharing for multiple videos.
A fix to the previous fix
Merge branch 'improvement/LL-831' into review

Conflicts:
	app/src/main/java/fi/aalto/legroup/achso/fragment/VideoBrowserFragment.java
Flush buffer properly when copying a file.
Build video state after the recorder responds.