keystone::wsgi::apache broken on Juno with Ubuntu 14.04

To make the WSGI version of Keystone work, the script relies on a Python file that creates the binding between Keystone and Apache. Ubuntu doesn't ship this WSGI file, which is available from https://raw.githubusercontent.com/openstack/keystone/stable/juno/httpd/keystone.py and thus puppet-keystone ships its own version of the file.

The file is outdated and will lead to Keystone reporting nothing but

Thu Feb 26 12:39:26.092551 2015] [:error] [pid 8183:tid 140330078480128] [remote 10.0.80.13:27177] mod_wsgi (pid=8183): Target WSGI script '/usr/lib/cgi-bin/keystone/main' cannot be loaded as Python module.
[Thu Feb 26 12:39:26.092585 2015] [:error] [pid 8183:tid 140330078480128] [remote 10.0.80.13:27177] mod_wsgi (pid=8183): Exception occurred processing WSGI script '/usr/lib/cgi-bin/keystone/main'.
[Thu Feb 26 12:39:26.092608 2015] [:error] [pid 8183:tid 140330078480128] [remote 10.0.80.13:27177] Traceback (most recent call last):
[Thu Feb 26 12:39:26.092623 2015] [:error] [pid 8183:tid 140330078480128] [remote 10.0.80.13:27177] File "/usr/lib/cgi-bin/keystone/main", line 42, in <module>
[Thu Feb 26 12:39:26.092644 2015] [:error] [pid 8183:tid 140330078480128] [remote 10.0.80.13:27177] config.setup_logging(CONF)

Due to its architecture, it's impossible to overwrite the path that the module will use to get the WSGI module. When using Keystone + mod_wsgi on Ubuntu with Juno, this module is thus fundamentally broken.