Feature suricata

Submitting a pull request to add Suricata stats gathering capability to collectd via Suricata's unix-command socket implementation.  This plugin opens a unix socket connection to a running Surcata IDS/IPS engine (when enabled with unix-comand: yes in the Suricata config).  This socket is polled with a json command set to gather statistics to be output via output plugins such as graphite.