Client capabilities, how to reference them?

[pajatopmr]

@fwcd I have discovered some issues with workspace and document symbols in that they do not comply with the spec constraints on using some or all of the symbol kinds and the document symbols request has some constraints as well. I will detail these issues in a subsequent report along with a PR to fix them. To that end, I need to access the client capabilities but as near as I can tell, they are not persisted as part of the Initialize request. Is it possible that I am missing something and there is some other way to access the client capabilities? I will proceed by adding a ClientConfiguration property to the Configuration class and create that property as part of initialize request processing. Do advise if you have some other preference. Thanks.