Don't allow push to live if staging revision starts with 'test-'

Force the start of the revision on staging to match "live-", rather
than matching "live-" anywhere in the string.
Make gollum launch/kill scripts cleaner

This fixes 3 things:

1. launch_gollum displaying an empty pid in the "Launching gollum
   with pid ...." message.
2. kill_gollum returning before gollum had actually closed down.
3. launch_gollum fails gracefully if netstat is not installed,
   instead of hanging forever.