Add host public key to known_hosts when using bosh ssh
Add host public key to known_hosts when using bosh ssh

[#102530088]
https://www.pivotaltracker.com/story/show/102530088

Signed-off-by: Nitin Ravindran <fc3e8387eefc4c2d705da57c4c4e7f7e6d026383@pivotal.io>

barthy1/bosh,barthy1/bosh,barthy1/bosh,barthy1/bosh