Don't pull the server unless we are on error mode
Don't pull the server unless we are on error mode

We now detect the error mode using the Websocket connection closing instead of
pulling the server regularly. This removes the potential server side effects
of responding to a new HTTP query every 500ms -- potentially a performance
intensive task if you have for example server-side rendering, and you may also
have some monitoring functions that would have been disturbed.

stubailo/meteor-dev-error-overlay