this does not need to be the unix epoch anymore
agent-id may not be set yet
implement proper last_master_contact calculation
unused kwargs -> _
adding last_announce
fixing tests for last_announce
add last_announce to /status
merging from #75
response.data() does not exist, use text
Merge pull request #77 from guidow/stop_bugfix

response.data() does not exist, use text
On stop, don't log out from master if ot logged in

This would just fail anyway, because we don't know our agent_id
Merge pull request #78 from guidow/logout_only_if_loggedin

On stop, don't log out from master if ot logged in
Introduce supervisor daemon for pyfarm-agent

This is the first step towards agent auto-updates. The supervisor
regularly checks if the agent is still running and, if not, restarts it.

If it finds an update in an update drop directory specified on the
command line, it will apply it before starting the agent.

Currently, applying an update just means unpacking a zip file to a
specified location.
Fix copy-paste error
Change default updates drop dir
Drop unneeded log statement
Make main loop interval configurable
Fix some log strings
Wrap actually updating the agent in a try-block
Forgot needed import