demo script updates (#934)

Demo script updates.  Record-replay, a bugfix in the canary demo script, etc.

demos/record-replay/hi.py

@@ -0,0 +1,7 @@
+from flask import request
+from flask import current_app
+
+
+def main():
+   name=request.args["name"]
+   return "Hello, %s" % name