Revert "io_timeout is used when the client or server is expected to make progress"
Revert "io_timeout is used when the client or server is expected to make progress"

This reverts commit c00b5731720bf96901bafd1205587cb4e71f45b5.

h2o/h2o,yannick/h2o,h2o/h2o,yannick/h2o,yannick/h2o,h2o/h2o,h2o/h2o,devnexen/h2o,devnexen/h2o,devnexen/h2o,yannick/h2o,devnexen/h2o,h2o/h2o,devnexen/h2o,yannick/h2o,h2o/h2o,h2o/h2o,yannick/h2o,h2o/h2o,devnexen/h2o,devnexen/h2o,devnexen/h2o,h2o/h2o,devnexen/h2o,yannick/h2o,yannick/h2o,yannick/h2o