Modernize o.e.dltk.ruby.formatter.

* Bump BREE to Java 1.6.
* Add missing @Override.
* Generify.
* Add missing copyright headers.
* Stricter compiler settings and enable save actions.

Change-Id: Ib28766dda16e2cea4d618fe34af4c1f79ca296cf
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>