Ipns name resolution

This branch is not yet complete, but before i move forward, the name resolution code (in namesys) needs some critiquing. There are also a decent number of bugfixes in this branch that i ran into while trying to get the code to a point where i could test ipns.
(btw, this command should be different from a `ipfs name publish <hash>` which should be the plumbing command of just `3.`)