Updates and fixes

- adding IsFirstHandler to allow controls to skip Actions which has been invoked already (i.e. due to navigation)
- adding Hidden method to ButtonGrid to fix re-rendering Buttons after opening a Modal form and comming back
- improving and fixing the Cleanup method for ButtonGrid to prevent "Keyboard jumping" for ReplyKeyboard on mobile devices.
- renaming some old *Result objects to *EventArgs for more clear definitions

TelegramBotBase/Base/MessageResult.cs

@@ -113,6 +113,11 @@ namespace TelegramBotBase.Base
             }
         }
 
+        /// <summary>
+        /// Returns if this message will be used on the first form or not.
+        /// </summary>
+        public bool IsFirstHandler { get; set; } = true;
+
         public bool Handled { get; set; } = false;
 
         public String RawData