Enable packaging at https://packager.io/gh/pkgr/statsd

This pull request enables automatic packaging of statsd for Debian/Ubuntu/CentOS/RHEL using packager.io. The packages come with init scripts and a facility to install additional npm modules if needed.

Example installation instructions at https://packager.io/gh/pkgr/statsd/install?bid=15#ubuntu-14-04-statsd