command not found errors on unstack

- add lib/ceilometer and lib/heat to source list for when stop_heat
and stop_ceilometer functions are called.
- add lib/tls source to lib/keystone for when is_ssl_enabled_service
function called.

Change-Id: Ief05766e9cfda71fb6392c8a757d04751283414e
Closes-Bug: #1269047
diff --git a/lib/keystone b/lib/keystone
index a7e5d66..ceefe6a 100644
--- a/lib/keystone
+++ b/lib/keystone
@@ -28,6 +28,7 @@
 XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 
+source $TOP_DIR/lib/tls
 
 # Defaults
 # --------