documentation/website and cleanup

Hi all,

Seems like the lack of good documentation is one of the main blockers of
banana-rdf adoption. I suggest that we should create static banana-rdf
website and put docs there. I do not care much about the technology unless
it is scala-based (no jekyll, pls). In my opition scalatext is the best
solution ( I even wrote some code
https://github.com/banana-rdf/banana-rdf/pull/290 ) but any scala-based
static generator will do. I also suggest to find some time to clean
outdated issues, it is not hard but will simplify further work a lot.

-- 
Best regards,
Anton Kulaga