Fixed backwards negation messages.
Fix issue #137, test message existence by using message!=null rather than using message
Merge pull request #138 from timnew/master

Fix defect #137 assertThrow always passes when message is empty
Merge pull request #136 from whatthejeff/message_fix

Fixed backwards negation messages.
Merge branch 'master' into feature/saucelabs

* master:
  Fix issue #137, test message existence by using message!=null rather than using message
  Fixed backwards negation messages.