This is similar to the deadlock bug in the proxy-go instances. If the
proxy-pair sends an answer to the broker, it previously assumed that the
datachannel would be opened and the pair reused only once the
datachannel closed. However, sometimes the datachannel never opens due
to ICE errors or a misbehaving/buggy client causing the proxy to
infinitely loop and the proxy-pair to remain active.
This commit reuses the pair.running attribute to indicate whether or not
the datachannel has been opened and sets a timeout to close the
proxy-pair if it has not been opened by that time.
Some files were omitted in the .eslintignore, left as an exercise to the
reader.
We probably want to reduce amount of globals overall and use proper es
modules.
