v0.1.5

• Added "onclose" event, which responds to EXPLICIT REQUESTS TO CLOSE THE CONNECTION. If you want a riskier metric (which will catch failures but may report false positives), then use "ondisconnect".
• Added "ondatachannel" event to tracked connection objects, this should fire when a data channel is added to a connection - in particular, when a received connection becomes ready for use.
• Added "ondisconnect" event to tracked connection objects, this should fire when a connection to another client terminates (either deliberately or on browser/node exit).
• Successive calls to .connectTo() will return the promise that was supplied on the first count.