Fix agent.blobstore.address description
Fix agent.blobstore.address description

[#140855057](https://www.pivotaltracker.com/story/show/140855057)

Signed-off-by: Mario Manno
cloudfoundry-incubator/bosh-openstack-cpi-release,cloudfoundry-incubator/bosh-openstack-cpi-release,cloudfoundry-incubator/bosh-openstack-cpi-release