Moved some extra features from POC-project to core library.
Made some changes to the Scenario class.
Fixed a clock-issue.
Internalized ScenarioClock.
Incremented the build-number.
Removed Execute method again.
Made Clock-property virtual and added some ScenarioClock-tests (which fixed a bug).
Improved the interface for verification a bit.
Merged External- and Internal Handlers into a single MessageHandler and improved the way the pipeline gets built.