Modernize o.e.dltk.ruby.core.tests.

* Bump BREE to Java 1.6.
* Add missing @Override and remove useless non-javadoc comments.
* Generify code.
* Switch Eclipse-LazyStart to Bundle-ActivationPolicy.
* Move away from deprecated method calls.
* Add missing copyright headers.
* Enable save actions to ease keeping the code cleaner.

Change-Id: Id0ad8d72c04134f1e99b5ab2df27edd08c618eaa
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>