Returning status_of_proc exit code for the status command.

See https://wiki.debian.org/LSBInitScripts/StatusSupport.

Since the debian init script doesn't use "set -e", the recommend appending this change for proper response codes. Without it, "service statsd stop" and "service statsd status" returns 0. With this, we get a return of 3. Helps with automated tests checking response codes.