Disabling/Disposing doesn't work once started without incoming resquests

[sebdg]

Hello,

I'm using Metrics.Net for a while now and since short I wanted to make it start/stop multiple times without unloading the AppDomain or process.
I see that the code is foreseen for such behavior.
Great work on the async part with cancellation token etc.

But there is still a caveat with the current nuget packaged version for 4.0
The Listener is blocking on its accept request and doesn't wan't to stop if there is no browser on the viz app.
I had to trick the system a bit by starting a WebRequest myself during the call to Dispose/DisableMetrics methods otherwise they are blocking forever.

Kind Regards