feat: move MC into Essentials

In order to solve some dependency issues that keep cropping up, MC
should be moved back into the Essentials repo and loaded automatically
on startup. This will allow for all plugins that use the MC Messengers
library to use the same version without fear of overwriting a dll due to
loading of plugin libraries.

src/PepperDash.Essentials.MobileControl/RoomBridges/MobileControlBridgeBase.cs

@@ -0,0 +1,130 @@
+using PepperDash.Core;
+using PepperDash.Essentials.AppServer.Messengers;
+using PepperDash.Essentials.Core.DeviceTypeInterfaces;
+using System;
+
+
+namespace PepperDash.Essentials
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public abstract class MobileControlBridgeBase : MessengerBase, IMobileControlRoomMessenger
+    {
+        public event EventHandler<EventArgs> UserCodeChanged;
+
+        public event EventHandler<EventArgs> UserPromptedForCode;
+
+        public event EventHandler<EventArgs> ClientJoined;
+
+        public event EventHandler<EventArgs> AppUrlChanged;
+
+        public IMobileControl Parent { get; private set; }
+
+        public string AppUrl { get; private set; }
+        public string UserCode { get; private set; }
+
+        public string QrCodeUrl { get; protected set; }
+
+        public string QrCodeChecksum { get; protected set; }
+
+        public string McServerUrl { get; private set; }
+
+        public abstract string RoomName { get; }
+
+        public abstract string RoomKey { get; }
+
+        protected MobileControlBridgeBase(string key, string messagePath)
+            : base(key, messagePath)
+        {
+        }
+
+        protected MobileControlBridgeBase(string key, string messagePath, IKeyName device)
+            : base(key, messagePath, device)
+        {
+        }
+
+        /// <summary>
+        /// Set the parent.  Does nothing else.  Override to add functionality such
+        /// as adding actions to parent
+        /// </summary>
+        /// <param name="parent"></param>
+        public virtual void AddParent(IMobileControl parent)
+        {
+            Parent = parent;
+
+            McServerUrl = Parent.ClientAppUrl;
+        }
+
+        /// <summary>
+        /// Sets the UserCode on the bridge object. Called from controller. A changed code will
+        /// fire method UserCodeChange.  Override that to handle changes
+        /// </summary>
+        /// <param name="code"></param>
+        public void SetUserCode(string code)
+        {
+            var changed = UserCode != code;
+            UserCode = code;
+            if (changed)
+            {
+                UserCodeChange();
+            }
+        }
+
+
+        /// <summary>
+        /// Sets the UserCode on the bridge object. Called from controller. A changed code will
+        /// fire method UserCodeChange.  Override that to handle changes
+        /// </summary>
+        /// <param name="code"></param>
+        /// <param name="qrChecksum">Checksum of the QR code. Used for Cisco codec branding command</param>
+        public void SetUserCode(string code, string qrChecksum)
+        {
+            QrCodeChecksum = qrChecksum;
+
+            SetUserCode(code);
+        }
+
+        public virtual void UpdateAppUrl(string url)
+        {
+            AppUrl = url;
+
+            var handler = AppUrlChanged;
+
+            if (handler == null) return;
+
+            handler(this, new EventArgs());
+        }
+
+        /// <summary>
+        /// Empty method in base class.  Override this to add functionality
+        /// when code changes
+        /// </summary>
+        protected virtual void UserCodeChange()
+        {
+            Debug.Console(1, this, "Server user code changed: {0}", UserCode);
+
+            var qrUrl = string.Format($"{Parent.Host}/api/rooms/{Parent.SystemUuid}/{RoomKey}/qr?x={new Random().Next()}");
+            QrCodeUrl = qrUrl;
+
+            Debug.Console(1, this, "Server user code changed: {0} - {1}", UserCode, qrUrl);
+
+            OnUserCodeChanged();
+        }
+
+        protected void OnUserCodeChanged()
+        {
+            UserCodeChanged?.Invoke(this, new EventArgs());
+        }
+
+        protected void OnUserPromptedForCode()
+        {
+            UserPromptedForCode?.Invoke(this, new EventArgs());
+        }
+
+        protected void OnClientJoined()
+        {
+            ClientJoined?.Invoke(this, new EventArgs());
+        }
+    }
+}