OCSADV-27: VoTableClient

This is a small PR containing VoTableClient. It uses the http commons client library to produce a method that returns a Future[CatalogProblem \/ ParsedVoResource] after making a call to one of the Gemini catalogs

A few rawtype warnings were removed as well
If one of these is not available and fails right away yet the other would have eventually succeeded, won't we miss getting the valid results?