rails 4.1 support
Merge pull request #67 from igas/rails41

rails 4.1 support
bump version to 2.3.1
update `rake db:seed_fu` description (minor)

The description of `rake db:seed_fu` erroneously referred to `rake db:seed`
Merge pull request #69 from george/patch-3

update `rake db:seed_fu` description (minor)