Bump version after publishing 0.0.0.
Refactor main function to decouple per-job tasks.
Add ability to tail *all* jobs.
Ensure that we exit cleanly without hanging.

We seem to be hanging sometimes during branch deletion if there is a race
with another process attempting to delete the same branch at the same time.

Belt & suspenders: use process.exit(0) to definitely exit in any case when
we are done.
Link to travis logs.
Improve README.