Added SmartText and inheritors SmartPlainText and SmartEmbedText which will replace CREmbed in the future

src/NadekoBot/Common/SmartText/SmartTextEmbedAuthor.cs

@@ -0,0 +1,13 @@
+using Newtonsoft.Json;
+
+namespace NadekoBot
+{
+    public class SmartTextEmbedAuthor
+    {
+        public string Name { get; set; }
+        public string IconUrl { get; set; }
+        [JsonProperty("icon_url")]
+        private string Icon_Url { set => IconUrl = value; }
+        public string Url { get; set; }
+    }
+}