Bug fix: need to include poll.css

Author: bnmnetp

runestone/poll/poll.py

@@ -24,7 +24,7 @@
 def setup(app):
     app.add_directive('poll',Poll)
     app.add_javascript('poll.js')
-
+    app.add_stylesheet('poll.css')
     app.add_node(PollNode, html=(visit_poll_node, depart_poll_node))