Management of script references

[kkokosa]

Currently, script references only mscorlib while it would be very nice to have possibly to reference any additional assembly.

[kkokosa]

In my oppinion it would be nice to add references by some script "meta-tag", analyzed and removed before compilation. Something like;

#r "System.Numerics.Vectors"

using System;

namespace Samples
{
    public class Echoer
    {
        public string Write(string message)
        {
            return message;
        }
    }
}

[norek]

As I described in PR I've put //#r tag instead of #r. Comment sign allow me to use Roslyn Walker. Basicly im looking for all comments and those which contains #r are parsed to script.