Finalise configuration of FindBugs

The following suppression are still in place.
FindBugs: EI,EI2 (immutable stuff, i.e. dates)         [code-rules.xml]
CheckStyle: "TODO"                                              [code-style.xml]
JUnit: Summary printing of "Skipped" tests             [.travis.sh]

All of which should be unsuppressed when Ed is ready.