Merge pull request #89 from jensweigele/feature_ImprovedMessagesForGenerics

Improved messages for assertions containing generics
Improved NUnit XML Output:
- Added Categories
- Fixed swapped values in Node "test-suite" of type "Fixture" ("executed" and "result" were swapped)
Merge branch 'betterNUnitXMLSupport' into LUCEBITversion