CF: Clear all recents position

- can be set to any of the 4 corners or disabled

Change-Id: I6eac540a8ee3e1a7de636972f8c88b9bb8036369

Conflicts:
	res/xml/preference_headers.xml
	src/com/oct/tentacles/SettingsActivity.java

Conflicts:
	res/xml/preference_headers.xml
	src/com/oct/tentacles/SettingsActivity.java