Adding scaled output option KARMA_SCALED_RANGE

* Allows one to scale users' karma points using a defined maximum.
* In order to replicate MeowMeowBeenz, one would set `KARMA_SCALED_RANGE` to `(1, 5)`.  This would make the user having the most points to have a calculated karma value of `5`, and all other users being distributed somewhere between `1` and `5` proportional to their raw karma value.