Add functionality to delete selected pages

Also adds a 'delete' function to ContentPersister that works
based off the PrimaryKey definition

Change-Id: If4d627e4a929eef43b95d00ee5a3daa272c224b1
Bump minVersion to ICS, not HoneyComb

Nobody really has HoneyComb anyway, and we can simply consider them
to be getting the GB experience.

Change-Id: Ibc48bde8cdd20fa8d3a63cb96415863bccab48a8