ILoggingBuilder enhancements

[bjorkstromm]

Now that #182 is merged, we should add a ILoggingBuilder extension for adding LanguageServerLoggerProvider.

We should also read the minimum logging level from the one provided via SetMinimumLevel on the LoggingBuilder.

//cc @david-driscoll

[bjorkstromm]

And remove the UseDefaultLoggingProvider from LanguageServerOptions.

[david-driscoll]

I say doooooo eeeiiiiitttt

[david-driscoll]

I think the goal here has been accomplished for the most part.