Use mod_version to clean-up apache version matching

This change uses mod_version (shipped by default on everything we care
about) to set-up version-specific config within apache rather than
within devstack scripts.

Clean up the horizon and keystone config file generation to use the
internal apache matching.

Since I6478db385fda2fa1c75ced12d3e886b2e1152852 the apache matching in
'functions' is actually duplicated.  just leave get_apache_version in
lib/apache as it is used for config-file name matching in there.

Change-Id: I6478db385fda2fa1c75ced12d3e886b2e1152852
Use correct WSGI dir on SUSE distros

The current default (/var/www) leads to:

AH01797: client denied by server configuration:
/var/www/keystone/admin

For /var/www the needed permissions on SUSE are not set.
For /srv/www/htdocs/ the permissions are correct on SUSE systems.

Change-Id: I3f2df896daecdfe510d45ff121af2a8433a4d5be
XenAPI: stackrc now depends on nproc

Install it automatically in the devstack DomU

Change-Id: Ie282dd128ebc92377d85800585962bc8767483fe
Merge "Use mod_version to clean-up apache version matching"
Merge "Use correct WSGI dir on SUSE distros"
Merge "XenAPI: stackrc now depends on nproc"
Configure endpoints to use SSL natively or via proxy

Configure nova, cinder, glance, swift and neutron to use SSL
on the endpoints using either SSL natively or via a TLS proxy
using stud.

To enable SSL via proxy, in local.conf add

ENABLED_SERVICES+=,tls-proxy

This will create a new test root CA, a subordinate CA and an SSL
server cert. It uses the value of hostname -f for the certificate
subject. The CA certicates are also added to the system CA bundle.

To enable SSL natively, in local.conf add:

USE_SSL=True

Native SSL by default will also use the devstack-generate root and
subordinate CA.

You can override this on a per-service basis by setting

<SERVICE>_SSL_CERT=/path/to/cert
<SERVICE>_SSL_KEY=/path/to/key
<SERVICE>_SSL_PATH=/path/to/ca

You should also set SERVICE_HOST to the FQDN of the host. This
value defaults to the host IP address.

Change-Id: I36fe56c063ca921131ad98439bd452cb135916ac
Closes-Bug: 1328226