Stop referencing nova HACKING guide

Since this originally came from nova, the docstrings referred to the
nova HACKING guide, now that this is a separate project refer to the
OpenStack HACKING guide instead.

Change-Id: I38c0791dfca73cf3ae114fc7292c41c0670a3987
Reviewed-on: https://review.openstack.org/29739
Reviewed-by: Sean Dague <sean@dague.net>
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins
Add .mailmap file

Add .mailmap file with my new prefered email address

Change-Id: I4b0d50a6bcab3cf3c74cdd64d9feed39f4280231
Reviewed-on: https://review.openstack.org/29740
Reviewed-by: Sean Dague <sean@dague.net>
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins