Manual capability add/del interactions via Openstack API
Finish implementing manual capability insertion through extended Capnet Openstack API. This takes the form of a special WFA that can listen for and handle cap add/del from the openstack API level. Sort of nontrivial because WFAs are isolated in a netns... so the interface might be file-based, or unix-piped from the outside. We mostly want this so users can view the capability set via the web UI, and do any manual things interactively. This is mostly admin utility, and also a huge demo tool. Pretty hard for people to try this on the cheap without it... because their alternative is CLI stuff or writing their own WFA.