node-nats can leave request timeouts active after closing

[aricart]

node-nats is not cleaning up request timeouts.
On close, all request timeouts should be canceled:

Client.prototype.clearMuxTimeouts = function() {
    if(this.respmux) {
        for (var p in this.respmux.requestMap) {
            if (this.respmux.requestMap.hasOwnProperty(p)) {
                this.cancelMuxRequest(p)
            }
        }
    }
}

[aricart]

Or for that matter subscriptions that specify a timeout.