Fix GHC Warnings

We have warnings turned on, so we may as well get to a clean base-state.
All of these type signatures came from the compiler's warning text
itself.
Similarly, the imports were listed as redundant.

Then there were a few name shadowings, mostly "s" and "init".

Finally, there were some unused variables from the pattern matches.

Fallback to direct initiate when no Jingle Message Initation support

Check for a message initiation supporting resource, if none then send to the
most available resource.

TODO: Should only send to most available resource that supports jingle rtp audio.