Add option for setting TTL for OSD cluster created using osd-provision.sh

[tplevko]

It would be handy if the user could set the default time limit for OSD clusters created using the osd-provision.sh script.

[rareddy]

do you see any API calls to control this?

[kornys]

we are able to patch expiration_timestamp like we do if someone run ./osd-provision.sh --extend-expiration ...