Reviving and updating an old feature request for filtered remote packet capture

[PeterDedecker]

Remote capture as suggested by @sitloongs is often not an option here on remote ends/vessels.

Add ability to do filtered packet capture on support.cgi

Easiest way to do this would be to filter your capture in Wireshark, its pretty simply to use the ip.addr==x.x.x.x command to look for specific hosts or networks in a large capture.