stheophil/wahlversprechen — pull request #15 by MarcHauptmann (2014-05-01 20:11:45+00:00)
Title: Improvement for Statement.create and fix for issue #9

`Statement.create` throws `IllegalArgumentException` when invalid statement is created by rated author.

To fix issue #9 I replaced the `List` for tags by a `Set`. This also eases dealing with tags since their order is no longer important.