Handle Misc default Requests - i.e. initialize, cancelRequest

[TylerLeonhardt]

We are getting Warnings thrown for not handling misc Requests that, it would seem, VSCode itself sends. We should handle these Requests.

So far we've seen:
cancelRequest
initialize

The cancelRequest one would be good for perf for sure.

[SydneyhSmith]

Closing as resolved

[TylerLeonhardt]

This will be fixed in Omnisharp transition