Remove demo directory (#369)

Author: dwalton76

README.rst

@@ -168,16 +168,10 @@ Support
     what you are trying to do and what you have tried. The issue template
     is in place to guide you through this process.
 
-Demo Robot
-    Laurens Valk of robot-square_ has been kind enough to allow us to
-    reference his excellent `EXPLOR3R`_ robot. Consider building the
-    `EXPLOR3R`_ and running the demo programs referenced below to get
-    familiar with what Python programs using this binding look like.
-
 Demo Code
-    There are `demo programs`_ that you can run to get acquainted with
-    this language binding. The programs are designed to work with the
-    `EXPLOR3R`_ robot.
+    There are several demo programs that you can run to get acquainted with
+    this language binding. The programs are available at
+    https://github.com/ev3dev/ev3dev-lang-python-demo
 
 Upgrading this Library
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