Allow binding apache to a specific IP address

Add a 'bind_host' parameter to keystone::wsgi::apache to allow binding
to a specific IP address.

Fixes Bug #1273697

Change-Id: I4e94336c15132900dbe42052e46d0c7f2e36f91f
Add ability to disable pki_setup

The enable_pki_setup parameter adds the ability to disable pki_setup,
allowing the user to manage the signing certificate himself.

Change-Id: Icb84e01adecdd3287ceb22defb9882f03ae8d96f
Closes-bug: #1278546
Merge "Add ability to disable pki_setup"
Merge "Allow binding apache to a specific IP address"
Deprecate bind_host parameter

Since Icehouse release, bind_host parameter has been deprecated for two
new flags: public_bind_host and admin_bind_host: http://git.io/RGao7w

This patch deprecates bind_host param and ensure backward compatibility
and configure Keystone using the two new flags.

Closes-bug: #1271269

Change-Id: I60db96fc99311280ae5051e1d9cfb5d46b3374a2
Signed-off-by: Emilien Macchi <emilien.macchi@enovance.com>