Fix for pants bootstrapping error caused by Wno-error=unused-command-line-argument-hard-error-in-future

Reviewed at https://rbcommons.com/s/twitter/r/562/
Fixed jaxb documentation formatting issues

Previously there were (mostly indentation) issues that were making Sphinx choke.

Testing Done:
Ran /build-support/bin/publish_docs.sh -o end examined output.

Bugs fixed 252

Reviewed at https://rbcommons.com/s/twitter/r/575/
Move the bang algorithm to GroupIterator - the sole user.

Testing Done:
PANTS_DEV=1 ./pants goal test tests::

Bugs closed: 255

Reviewed at https://rbcommons.com/s/twitter/r/580/
Merge branch 'master' into stuhood/fix-antlr-gen-task
Review feedback