Add README to and fix Circle Pop demo

Circle Pop gets its own commit since I found a bug that had to be fixed

visual_script/circle_pop/README.md

@@ -0,0 +1,13 @@
+# Circle Pop
+
+Demo of a simple game using visual script.
+You must click the circles to "pop" them in
+order to stop their invasion of the screen. 
+
+Language: [VisualScript](https://docs.godotengine.org/en/latest/getting_started/scripting/visual_script/index.html)
+
+Renderer: GLES 2
+
+## Screenshots
+
+![Screenshot](screenshots/circle.png)