Merge pull request #18 from GrimmiMeloni/master

adjusted
Add failing test for issue #16.
GrahamA: surgically remove parts of findbugs that intern xclass stuff, for issue #16.
stop using gleclaire/findbugs-2.0.2

now FindBugs 2.0.2 is on Maven central, we do not
have to clone and install this unofficial repository.
Merge pull request #21 from eller86/stop-heavy-initialization

stop using gleclaire/findbugs-2.0.2
Merge pull request #1 from youdevise/master

update with Graham's master