start of rollers
Added new exceptions

ImpossibleException now gives a message for users to email me
Added MissingRangeException
Started OverlappingRangesException
Merge branch 'ftr/diceModel' of github.com:sad2project/UDiceSystem into ftr/diceModel
Merge branch 'ftr/rollers' of github.com:sad2project/UDiceSystem into ftr/diceModel