Ensure rbd connect exception is properly caught

[OpenStack Infra]

https://review.openstack.org/132336
commit 4a14db7a7477ef85d8cb57109cdc17763fba2917
Author: Edward Hope-Morley <email address hidden>
Date: Sun Jun 29 19:08:46 2014 +0100

    Ensure rbd connect exception is properly caught

    If the rbd driver fails to connect to Ceph the exception
    was not being properly caught resulting in the volume
    remaining in the 'creating' state until the corresponding
    task eventually times out (on top of the time it took
    for the connect to fail).

    Also added config option for rados connect timeout.

    Conflicts:
        cinder/volume/drivers/rbd.py
        etc/cinder/cinder.conf.sample

    DocImpact: new config option 'rados_connect_timout'
    (cherry picked from commit 02e4afbd8108ca26af09ccaebb8b1c8b72ea3f3f)
    Change-Id: I5e6eaaaf6bed3e139ff476ecf9510ebe214a83f9

[Tom Fifield (fifieldt)]

This will be picked up in the next run of autogenerate-config-docs

[Tom Fifield (fifieldt)]

This was picked up by the recent autogenerate-config-doc run.