CephContext now is capable of dealing with a space separated list of IPs
in the ceph-public-address field of the relation with ceph. This allows
ceph-proxy to pass a list of monitor hosts instead of a single one.
Change-Id: I83abc2c151636aea0b5dffc32f2e3c91acb7558b
Partial-Bug: 1642430
Closes-Bug: 1670223
896ea18db0