Support cquery's more granular semantic highlighting symbol kinds

This is https://github.com/cquery-project/cquery/pull/347 moved to this project.

I have addressed the suggestion of setting some defaults for bold and italic and such.

I'm not sure if we have come to a consensus about the naming of prefs.

I personally would think the following would make the most sense:

  "cquery.highlighting.types": {
    "enabled": true,
    "bold": true,
    "italic": false,
    "colors": [
      ...
    ]
  },
  "cquery.highlighting.functions": {
      ...
  },

Not sure if that's possible with vscode. In any case, perhaps this kind of refactoring could be left to a subsequent patch?

cquery-project / vscode-cquery

Support cquery's more granular semantic highlighting symbol kinds #1