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.Messengers/MobileControlMessage.cs

@@ -0,0 +1,23 @@
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using PepperDash.Essentials.Core.DeviceTypeInterfaces;
+
+namespace PepperDash.Essentials.AppServer.Messengers
+{
+
+#if SERIES4
+    public class MobileControlMessage : IMobileControlMessage
+#else
+    public class MobileControlMessage
+#endif
+    {
+        [JsonProperty("type")]
+        public string Type { get; set; }
+
+        [JsonProperty("clientId")]
+        public string ClientId { get; set; }
+
+        [JsonProperty("content")]
+        public JToken Content { get; set; }
+    }
+}