* Integrate SpotBugs (FindBugs) into build. Set ignoreFailures so spotted bugs do not break the build.
* Fix many SpotBugs-found items, mostly making things final, but also a redundant null check and a reliance on platform character encoding. 2 items remain which will need further work/review, but as ignoreFailures is set, they will not fail the check stage.
Co-authored-by: Trask Stalnaker <trask.stalnaker@gmail.com>
John Bley