Disable DotNetProjectSystem by default

[DustinCampbell]

This change threads through a new IProjectSystem.EnabledByDefault property and sets it to false for the legacy project.json project system.

[DustinCampbell]

Note: I submitted this change based on the conversation we had during the last OmniSharp call. If this is not what we want, we can just set EnabledByDefault to true for the DotNetProjectSystem. Having the mechanism is still nice. 😄

[filipw]

We also have a first level of configuration via an optional config.json file loaded here.

We used to ship it in the past, but then at some point it got lost (I really don't know what happened to it, I think it genuinely got lost) and it's not there anymore (though it was only setting some defaults for dotnet project system AFAIR and the defaults are hardcoded anyway).

So technically the same effect could be achieved by re-shipping the config.json at OmniSharp root again, with the following content:

{
  "dotnet": {
     "enabled": false
  }
}

Regardless, I'm voting with my hand and feet to have the dotnet project system disabled by default 😀

[david-driscoll]

Makes sense to me

[filipw]

LGTM!

[filipw]

@DustinCampbell looks like one file has conflicts, would you mind resolving?

[filipw]

that one is a good reason to celebrate 😃