EPIPE no longer ignored

For whatever reason, I had set up the AJP, FastCGI and SCGI servers to ignore EPIPE exceptions. (The exception that's thrown when writing to a disconnected socket, i.e. a web client that cancels a web page load or a download.) I think I had written the original version of fcgi (which I had written a millennia ago, it feels like), to do this... and since it was the basis for all the other servers... I never really questioned why EPIPE was being ignored. (To save the application from having to handle it?) I guess I just never tried downloading large files and then subsequently cancelling.

Anyhow, that behavior's been changed. It's still being ignored, but at a higher level. What this means is that WSGI applications may possibly see EPIPE socket.error exceptions, especially if they use the WSGI write callable. Also, the servers will stop iterating over the application's iterator should an EPIPE exception be thrown. (Which seems to be the correct thing to do anyway.)

Thanks to Ivan Sagalaev for bringing the problem to my attention!