Watchdog for ONIContextTask.ReadFrame()

[jonnew]

I wonder if it would be wise to remove the enable/disable stream register from the Heartbeat device so that ONIContextTask.ReadFrame() could have a hardware-based watchdog, like the following:

public oni.Frame ReadFrame()
{
    if (Monitor.TryEnter(readLock, new TimeSpan(0, 0, 1)))
    {
        try
        {
            return ctx.ReadFrame();
        }
        finally
        {
            Monitor.Exit(readLock);
        }
    }
    else
    {
        throw new Bonsai.WorkflowRuntimeException("Host lost heartbeat.");
    }
}

This may be is just a band aid over a more fundamental problem with RIFFA, and is only required because of issues with RIFFA.