Add :offset option to fuzzy find method.

It is often required to paginate the results of a search, but
fuzzily doesn't support an offset. An offset parameter was added that
is very similar to the limit parameter, and relies on the ActiveRecord
offset facility.
Add named_scope for offset in ActiveRecord 2
Put named_scope inside of a self.extended call in Rails2ClassMethods
Check for existence of :named_scope? before defining one
Define Rails3ClassMethods so that named_scope is not called in activerecord 3
Add @rickbutton to README
Merge pull request #25 from rickbutton/search-offset

Add :offset option to fuzzy find method.