package/snort3: new package

package/snort3: new package

Snort 3 is the next generation Snort IPS (Intrusion
Prevention System).

 - Support multiple packet processing threads
 - Shared configuration and attribute table
 - Use a simple, scriptable configuration
 - Make key components pluggable
 - Autodetect services for portless configuration
 - Support sticky buffers in rules
 - Autogenerate reference documentation
 - Provide better cross platform support

https://www.snort.org/snort3

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Reviewed-by: Heiko Thiery <heiko.thiery@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>