Heat autoscaling scenario test

This test starts with a single server and scales up to
three servers triggered by a script that consumes memory.

Seven minutes after stack creation, memory consumption script
will quit and the scale down alarms will scale back down to
a single server.

Due to the nature of this test, it takes about 10 minutes to
run locally.

The scenario test has been put in package orchestration
for the following reasons:
- this will be the first of many heat scenario tests
- this will allow a tox filter to run this test for the
  slow heat gating job

Change-Id: I53ed12369d12b902108b9b8fa7885df34f6ab51f
diff --git a/requirements.txt b/requirements.txt
index cc61b01..06db0e6 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -13,6 +13,7 @@
 python-novaclient>=2.10.0
 python-neutronclient>=2.2.3,<3.0.0
 python-cinderclient>=1.0.4
+python-heatclient>=0.2.3
 testresources
 keyring
 testrepository