Trying to track down corrupt database / items disappearing

Trying to track down corrupt database / items disappearing

-> Adding logs for all database transactions
-> Adding sanity checks for items in folders, throwing exceptions
   if they are violated
-> Reducing database upates when re-arranging items, only
   update if values have changed
-> Removed some dead code from ItemInfo (isGesture?)

Change-Id: Ia5cd57d92082f633dbf4aa5d64612cbae2d82bb4