fix horizon packages name typo on SUSE

Change-Id: I0c0425b5b6e6b6922114d4800fef4b0422a4d32c
Do not configure memcache if no servers found

If a user specified memcache as the session_backend for the dashboard
then make sure we have memcache servers to configure local_settings.py
with. Attempting to configure this Django front-end with memcache on
and no servers found/specified will cause Django to 500. But, that is
not to say that this configuration is an error - this could happen as
the environment is being converged across nodes.

This change adds tests to support this logic.

Change-Id: I72cf5465d09aec34d9a76305819745b0580b19a2
Support our own apache access/error log names

It looks like the apache cookbook does not set a default access_log
attribute. Even if it did, it would probably be too generic for anyone
wanting to isolate access logs for openstack-dashboard. Similarly,
So, move this attribute into our own namespace and set the default as
"openstack-dashboard-access.log". As error logs fall into the same
dilemna, maintain consistency by also configuring their naming inside
this cookbook.

Change-Id: Iaa7c4202a14c6e3a963cb1bc5f37239c847264b0
Merge "Support our own apache access/error log names"
Merge "fix horizon packages name typo on SUSE"