LSP: New settings option to Disable server and Better Goto Definition for property and file paths (1/2)

[wolmir]

This PR will allow the Goto Definition for feature for properties inside parameter files, and also for files referenced in the dvc.yaml.

It will also introduce an extension setting to disable the language server when needed.

Demo:

https://user-images.githubusercontent.com/1231848/193884449-272037d5-6aa5-4f6c-82bc-61f29cd643ad.mov

[qlty-cloud-legacy[bot]]

Code Climate has analyzed commit 92e616fa and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 88.4% (85% is the threshold).

This pull request will bring the total coverage in the repository to 96.6% (-0.2% change).

View more on Code Climate.

[mattseddon]

Needs #2530 to be ready before merging.