Fix readme to reflect new bosh add-on way of deploying drivers [#120977577](https://www.pivotaltracker.com/story/show/120977577)
Fix readme to reflect new bosh add-on way of deploying drivers
[#120977577](https://www.pivotaltracker.com/story/show/120977577)

Signed-off-by: Paul Warren <381ebbe39e97b92332c450533d9eabb9a873db86@emc.com>

cloudfoundry-incubator/cephfs-bosh-release,cloudfoundry-incubator/cephfs-bosh-release