Uncaught exceptions

fixes #211 : Major refactoring in order to enable a services concept.

The implemented ThreadService is not thread-safe yet.

Merging of SignalingCounter still missing!

See merge request !49

Conflicts:
	src/main/java/teetime/framework/ThreadService.java

fixed javadoc issues

New context concept

See merge request !50

filtered stages visiting at runtime

Conflicts:
	src/main/java/teetime/framework/Execution.java