statsd.upstart: exec to remove parent shell from process list

Changes ps output from:

1234 _statsd sh
1235 _statsd \_ statsd /etc/statsd/localConfig.js

to just one second line without intermediate shell process waiting for node.
Merge pull request #429 from temoto/patch-1

statsd.upstart: exec to remove parent shell from process list
Merge pull request #1 from etsy/master

Pull in Upstream Changes