Allow installation of source bundles.
Fix requires generation bug

Requires on internal units were generated only with debugging enabled.
[test] Add test for self-dependencies
[test] Remove self-dependency expectation assertions
Don't generate dropin self-requirements

OSGi requirements that are satisfiable by units available in the same
dropin shouldn't be propagated as RPM requires.
Add some basic debugging information and minor fixes.

- Bundles and Features indexed
- Duplicate content
- Use getenv() for JAVACONFDIRS