Pmd fixes

major overhaul with tons of PMD fixes

See merge request !80

Runtime pipe check

check is executed upon onStarting... it just takes a look at the type of the output port and compares it to the input port
A Test for a false connection can't be done without a DSL or such, as the generics prohibit a false connection in the IDE.

See merge request !78

Conflicts:
	src/test/java/teetime/framework/AbstractStageTest.java
	src/test/java/teetime/stage/basic/merger/MergerSignalTest.java

Fixes #260

As the merger does not have any separated logic anymore, the tests can
be moved to AStageTest

See merge request !79

As the merger does not have any separated logic anymore, the tests can
be moved to AStageTest