@jbenet

The pkg.Interface style is modeled after heap.Interface. Generally, I
find it helpful for interfaces that have many implementations. It
provides clear distinction between the generic interface and the |n|
implementations that implement it (which may be interface types
themselves).

For clients who cannot keep the repo name, one can imagine that the most
likely rename is `ipfsrepo`. In that case, `ipfsrepo.Interface` remains
meaningful.

This is low-pri so it doesn't matter than much. But for the record, the
repo.Interface feels appropriate in this use-case.

@jbenet

@jbenet this removes everything under the path

This may have been failing before.

let me know if this looks off @whyrusleeping @jbenet

it's unclear what this test case is meant to protect, but passing an empty datastore value no longer has bearing on node construction. Datastore setup now occurs in repo.

p2p/net/swarm: fixed bugs in swarm err closes

p2p/net/swarm: dial once at a time

p2p/net/swarm: fix connect self problems