fix(store): list all monitors in [global] section of config

This is due to a Ceph bug - http://tracker.ceph.com/issues/10012.
Some configuration options aren't read properly if they're not in
the `[global]` section of the Ceph config. This means that the
store-gateway component was only connecting to the initial monitor,
instead of using all the enumerated monitors.

This notation is functionally equivalent, so it'll work just fine
for us.
fix(store-gateway): don't log to stdout

Since we're not execing the radosgw daemon, its view of /dev/stdout
is not really stdout, resulting in the logs being eaten. Now they'll
at least be on the filesystem should debugging be necessary.
Merge pull request #2724 from carmstrong/store-fix_hosts

fix(store): list all monitors in [global] section of config