Add lint groups to Q#

[orpuente-MS]

This PR adds the necessary infrastructure to define lint groups. It also adds the deprecation lint group, which allows the user to enable all deprecation lints at the same time, which are set to allow by default.

A lint group can be added to the qsharp.json manifest as follows:

{
   "lints": [
      { "group": "deprecations", "level": "warn" }
   ]
}

[minestarks]

Should we update our qsharp.json schema? ( vscode\qsharp.schema.json )

[orpuente-MS]

@microsoft-github-policy-service rerun