Validate I don't have dangling slash links in my sphere

[justinabrahms]

It's possible to generate a local slashlink which doesn't have a backing file. orb should be able to detect this through some sort of link checking operation.

[cdata]

Yah, I've thought it would be nice to have a "resolve" command in orb so that you can do one-time, on-demand lookup of e.g., a slashlink or a peer address. This is a great example of why that would be useful.