Replace ScriptCs by dotnet script

[laedit]

Since ScriptCs doesn't support netstandard.

https://github.com/filipw/dotnet-script

[biohazard999]

Had a quick look into the gut's of dotnet-script guts and it's doable, but requires a lot of work.
Another one for after #347

[laedit]

Finally, I wonder if we should keep this feature since it allows to run code that the user doesn't own and can be modified without his consent.
Or am I too paranoid?

[biohazard999]

Maybe paranoid, Maybe both. If plugin provisioning is easy with #348 the script feature would be maxiumum a nice to have. Probably we drop support for it now and focus on netcore and bring it back later. I don't know.

[laedit]

Probably we drop support for it now and focus on netcore and bring it back later.

I agree.