http: fix detecting EOF without write Before this patch http server don't knows when client disconnected until it will try to write to it, IOW to detect is client still alive you need to write something to client socket, however it is not convenient since it requires to store all clients somewhere and poll them periodically, and I don't see any regressions if we will leave EV_READ always (like libevhtp do), since we already reset read callback in evhttp_write_buffer() (see http/write_during_read). Also since we don't disable EV_READ anymore we don't need some enable EV_READ, so we will reduce number of epoll_ctl() calls. Covered-by: http/terminate_chunked_oneshot Covered-by: http/write_during_read Fixes: #78