Syntax highlighting could use improvement

[minestarks]

The TextMate grammar used for Q# syntax highlighting in VS Code is missing some patterns that would help the syntax highlighting look nicer.

Compare:

The Q# looks pretty boring in comparison to other languages with good support.

I think we can start by defining patterns for function calls and numeric literals, which are seen in these screenshots. There may be others that are interesting as well.

[Morcifer]

Hi @minestarks, @sezna, can I pick this one up?

I managed to get the function (and operation) definitions working, at least. But there's a tendency here for things to get fixed in one spot and then break in another if you're not careful, so this fix might require small changes to existing patterns as well...

(this comment was edited several times, sorry about that).