added a few more basic unit-tests for Examples. This is supposed to catch future failures of this type.

 On branch 188-sibyll-decay-of-sigmabar0-yields-sigmabar0
 You are currently cherry-picking commit 9c650baf.

 Changes to be committed:
	modified:   Documentation/Examples/boundary_example.cc
	modified:   Documentation/Examples/cascade_example.cc
	modified:   Documentation/Examples/vertical_EAS.cc
	modified:   Processes/Sibyll/Decay.cc
	modified:   Processes/Sibyll/Decay.h
	modified:   Processes/Sibyll/Interaction.cc
	modified:   Processes/Sibyll/Interaction.h
	modified:   Processes/Sibyll/sibyll2.3c.f
	modified:   Processes/Sibyll/testSibyll.cc