Update devstack's Tempest integration

Split build_ci_config.sh into:
* tools/build_tempest.sh - checks out Tempest and installs prereqs
* tools/configure_tempest.sh - creates tempest.conf from devstack

Change-Id: I22f40226afb617a5a6e32f2631b07d5509f10b13
diff --git a/stackrc b/stackrc
index ce34971..acc5ac0 100644
--- a/stackrc
+++ b/stackrc
@@ -42,9 +42,9 @@
 QUANTUM_CLIENT_REPO=https://github.com/openstack/python-quantumclient
 QUANTUM_CLIENT_BRANCH=master
 
-# CI test suite
-CITEST_REPO=https://github.com/openstack/tempest.git
-CITEST_BRANCH=master
+# Tempest test suite
+TEMPEST_REPO=https://github.com/openstack/tempest.git
+TEMPEST_BRANCH=master
 
 # Specify a comma-separated list of uec images to download and install into glance.
 # supported urls here are: