Isolate sudo syslog logs locally

W/o this fix sudo messages from Openstack root-wrappers are *too*
numerous and just flooding the network around and consume additional
space at the remote log server.

The solution is do not send sudo logs remotely, but store them locally
instead.
* Add new /var/log/sudo.log file for sudo logs at Openstack nodes
* Add /var/log/sudo.log to rotation plans as well.

DocImpact
Closes-bug: #1390376

Change-Id: Ife1cb9d6c342966d09329745c8dfeb96e15737be
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Merge "Isolate sudo syslog logs locally"