Better upstart script

Add a stop stanzas
(http://upstart.ubuntu.com/cookbook/#job-with-start-on-but-no-stop-on)
and use start-stop-daemon as recommended in the upstart cookbook
(http://upstart.ubuntu.com/cookbook/#changing-user)
Revert "Better upstart script"

This reverts commit 7a41dea8931e3ff9910c183eea2376a4a4add90f.
Keeps only the stop stanza
Merge pull request #120 from dbathily/master

Better upstart script