Upgrade findbugs to spotbugs for 1.9

(Backport of #615 to the 1.9 branch with some updates)

* Upgrade findbugs to spotbugs 3.1.6
* Rename all findbugs to spotbugs (with various capitalizations)
* Remove README.spotbugs/README.findbugs (contains incorrect info and not useful)
1 file changed
tree: 81057ea3cba432e419fac821fa20b051bfbaa2a9
  1. examples/
  2. src/
  3. .gitignore
  4. pom.xml
  5. proxy.properties
  6. README