WIP - level up libp2p interface and error handling

[daviddias]

• requires level up libp2p functionality js-libp2p-ipfs-nodejs#9
• requires fix the close event for when a conn is destroyed libp2p/js-libp2p-webrtc-star#2

[coveralls]

Coverage decreased (-31.1%) to 39.45% when pulling d57b48dd006b1730934c02abb88be3fa4e9016a4 on level-up into 6e2c06a on master.

[dignifiedquire]

This has massive amounts of duplicated code with js-libp2p-ipfs can we please figure out a way to share this code between these two modules?

[daviddias]

@dignifiedquire agree, I've been thinking about it, just afraid of the implications which is coming up with with the interface that does the bindings not adding even more dup/dumb code then what we have already.

(It is also hard to clean the interface until we have the Peer Routing and Content Routing completely ready)

[coveralls]

Coverage increased (+4.0%) to 74.561% when pulling 7f0a0db on level-up into 6e2c06a on master.