C#: Add Ide Connection library and server for the editor

This will be used for communicating between the Godot editor and external IDEs/editors, for things like opening files, triggering hot-reload and running the game with a debugger attached.

modules/mono/editor/GodotTools/GodotTools.IdeConnection/MessageParser.cs

@@ -0,0 +1,88 @@
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace GodotTools.IdeConnection
+{
+    public static class MessageParser
+    {
+        public static bool TryParse(string messageLine, out Message message)
+        {
+            var arguments = new List<string>();
+            var stringBuilder = new StringBuilder();
+
+            bool expectingArgument = true;
+
+            for (int i = 0; i < messageLine.Length; i++)
+            {
+                char @char = messageLine[i];
+
+                if (@char == ',')
+                {
+                    if (expectingArgument)
+                        arguments.Add(string.Empty);
+
+                    expectingArgument = true;
+                    continue;
+                }
+
+                bool quoted = false;
+
+                if (messageLine[i] == '"')
+                {
+                    quoted = true;
+                    i++;
+                }
+
+                while (i < messageLine.Length)
+                {
+                    @char = messageLine[i];
+                    
+                    if (quoted && @char == '"')
+                    {
+                        i++;
+                        break;
+                    }
+
+                    if (@char == '\\')
+                    {
+                        i++;
+                        if (i < messageLine.Length)
+                            break;
+
+                        stringBuilder.Append(messageLine[i]);
+                    }
+                    else if (!quoted && @char == ',')
+                    {
+                        break; // We don't increment the counter to allow the colon to be parsed after this
+                    }
+                    else
+                    {
+                        stringBuilder.Append(@char);
+                    }
+                    
+                    i++;
+                }
+                
+                arguments.Add(stringBuilder.ToString());
+                stringBuilder.Clear();
+
+                expectingArgument = false;
+            }
+
+            if (arguments.Count == 0)
+            {
+                message = new Message();
+                return false;
+            }
+
+            message = new Message
+            {
+                Id = arguments[0],
+                Arguments = arguments.Skip(1).ToArray()
+            };
+
+            return true;
+        }
+    }
+}