Conflicts:
	src/test/java/teetime/framework/RunnableConsumerStageTestConfiguration.java

both uses the context now

Connector survey

See merge request !44

added null checks

Conflicts:
	src/main/java/teetime/framework/pipe/InstantiationPipe.java

threadableStages list

Nested compositestages

finished the new method which works with nested composite stages.
Tested with kieker-teetime-stages (already adapted) and kieker-trace-diagnosis (after adaption).

See merge request !42