Convert Main.Run to an instance method. Convert locals to fields.

This will prepare us to be able to extract out classes.

csharp/BrainmessShort/Main.cs

@@ -5,18 +5,24 @@ namespace BrainmessShort
{
   public class Brainmess
   {
        private readonly string program;
        private int pc = 0;
        private readonly int[] tape = new int[5000];
        private int tc = 2500;
        public Brainmess(string program) 
        {
            this.program = program;
        }
        
        public static void Main(string[] args)
        {       
            var reader = File.OpenText(args[0]);
            Run(reader.ReadToEnd());
            new Brainmess(reader.ReadToEnd()).Run();
            reader.Close();
        }
        
        public static void Run(string program) 
        public void Run() 
        {
            int pc = 0;
            int[] tape = new int[5000];
            int tc = 2500;
            while(pc < program.Length)
            {
                char instruction = program[pc];