Add log_dir param. by default and allow users to disable it

This commit add log_dir param and configures it to /var/log/keystone
(default location). Set log_dir to false allows users to disable logging
to a directory (usefull if syslog is enabled in order not to log twice).

(cherry picked from commit 5a48d7d4fb0916695f6a8d29db47f46123398ee0)
Change-Id: I83446ff8b70c1cc136c9e1bb24513006ac9cb5a8
Closes-bug: #1282296
Merge "Add log_dir param. by default and allow users to disable it" into stable/havana
keystone-client: update endpoint argument

Endpoint argument is now os-endpoint: http://git.io/dVjoPg

Change-Id: Ibe43dc4e55fd315ee9e6dc7d68606efdae57476a
Signed-off-by: Emilien Macchi <emilien.macchi@enovance.com>
(cherry picked from commit bea3a92c5658cd1245f33f344bc841932f68b043)
Merge branch 'stable/havana' of https://github.com/stackforge/puppet-keystone into havana