Make `var` explicit/implicit about csharpextensions

[KreativJos]

Editorconfig rules can be enforced, can't they? At least via Pull Requests etc, but it should be possible via git hooks.
To handle changing vars to explicit typings requires knowledge of the language in parsing, not just a simple regular expression. That is a bit too much for me to develop. But if someone would make a PR, I'd be happy to review & test.

[KreativJos]

Isn't that already covered with omnisharp in .editorconfig rules?
https://docs.microsoft.com/en-us/dotnet/fundamentals/code-analysis/style-rules/ide0007-ide0008

I'm guessing you'd want something like this:

csharp_style_var_elsewhere = false:warning
csharp_style_var_for_built_in_types = true:suggestion
csharp_style_var_when_type_is_apparent = true:suggestion

To ensure messages / warnings are created, and have vscode still running smoothly, I had to add an omnisharp.json to the root of my solution with the following contents:

{
    "RoslynExtensionsOptions": {
        "EnableAnalyzersSupport": true
    },
    "FormattingOptions": {
        "EnableEditorConfigSupport": true
    }
}

And I added these to my vscode settings:

"omnisharp.enableAsyncCompletion": true,
"omnisharp.enableRoslynAnalyzers": true,

[ipsquiggle]

Oh neat, I hadn't come across that particular rule! Thanks. 👍

In the case that a person isn't using enforced rules though, it would still be nice to be able to flip back and forth between var and explicit using the quickfix menu.