Clean slate project for easy adoption

[PedroWitzel]

My first expectation when coming to this project was to have an empty-shell project that I could add my own stuff.
But it's also good to see some implementation as example, it help me a lot to understand on how to use Tower LSP.

Would you be interested into having a branch where there's no actual code, but only the boiler-plate needed to start up and build the LSP project ?
The goal being that people could fork the project and build up from there.

I have a branch on my fork like this, so I could open a PR if you like.
I didn't implement all functions given be the LanguageServer, but it might be nice.