This adds async poll support to playbooks. See examples. Some more testing due + docs

but this is more or less a mirror of what /bin/ansible does.  It also has a 'fire and
forget' mode if the poll interval is left off or set to 0.

examples/playbook.yml

@@ -5,6 +5,10 @@
     http_port: 80
     max_clients: 200
   tasks:
+  - name: simulate long running op (15 sec), wait for up to 45, poll every 5
+    action: command /bin/sleep 15
+    async: 45
+    poll: 5
   - include: base.yml favcolor=blue
   - name: write the foo config file using vars set above
     action: template src=foo.j2 dest=/etc/some_random_foo.conf