Traceable inheritance.

It works similarly to `find` command found on some systems but with less options and potentially more speed. I've seen some other utilities doing this but this is pretty good and the source should be easy to understand if you decide to look at it.

Cradle 0.6.9 with support for a path in host, see ihttps://github.com/flatiron/cradle/pull/284, High-level, caching, CouchDB library