KbDbHelper is now a singleton
Fixed crash condition
Fixed - task 355: [feature] batch su access when saving a reference 
https://github.com/asksven/BetterBatteryStats/issues/issue/355
Added roottools to readme
Fixed - task 402: [bug] wakelock account masking causes "clone" to
recalculate the hash, leading to the same wakelock having a different
name due to double hashing 
https://github.com/asksven/BetterBatteryStats/issues/issue/402
Commit for release