Potential deadlock in abort

[JoTurk]

Hi, I am currently investigating a peerConnection.Close() that hang forever in some rare case which create a leak and let a lot of buffer taking ram forever

digging deeper into it with pprof, the peerConnection.Close now default to call the association.Abort and it get stuck here:
// Wait for readLoop to end
<-a.readLoopCloseCh

I am still unable to reproduce the issue manually, and it may take 2 hours of spamming over 20 concurrent webrtc connections for it to happen
The association.go use the dtl connection

Do you think it could be related?

Originally posted by @craymond12 in #667

I think it still happens after #709

[JoTurk]

@craymond12 I think this was resolved by #709 if you it still happens to you please re-open the issue and we'll solve it!