Better init of CleaningStats
Using clean_none to indicate error in cleaning selection
Cleaning up reduceDB
Don't clean recent 2-glue redundant clauses
Renaming function
Less implicit stat checking
Fixing function name
Renaming function
Removing const from function header when passing param as-is

It's not needed:
http://stackoverflow.com/questions/117293/use-of-const-for-function-parameters

It allows me to have the implementation be different. From a compilation
perspective, it's the same thing and both are accepted.

Fixes #183