Updated README.md

Specify that this plugin only works on QGIS 2 and add a link to the QGIS 3 compatible plugin

Author: Maaka2890

README.md

@@ -1,5 +1,6 @@
-# BoundingBox
-This QGIS plugin returns the xmin, ymin, xmax, ymax and the GetMap request of the current view window of the selected WMS.
+# BoundingBox Plugin for QGIS 2
+This QGIS 2 plugin returns the xmin, ymin, xmax, ymax and the GetMap request of the current view window of the selected WMS.
+For this plugin compatible with QGIS version 3.4 or higher go to: https://github.com/Maaka2890/BBox3
 
 Developers of web services often need bounding boxes of specific areas during trouble shooting, for test calls or for communication. 
 The goal of this plugin is to, with one click, provide the bounding box of the current view window and the GetMap request of the selected WMS. You can copy this for your tests. 
@@ -16,4 +17,4 @@ This plugin was created using Plugin Builder, Qt Creator and python.
 For more information, see the PyQGIS Developer Cookbook at:
 http://www.qgis.org/pyqgis-cookbook/index.html
 
-This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.
+This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.