Merge branch 'master' into copy

Conflicts FIXED:
	src/com/owncloud/android/ui/activity/FileDisplayActivity.java
	src/com/owncloud/android/ui/fragment/OCFileListFragment.java
	src/com/owncloud/android/ui/preview/FileDownloadFragment.java
	src/com/owncloud/android/ui/preview/PreviewImageFragment.java
	src/com/owncloud/android/ui/preview/PreviewMediaFragment.java