Consider supporting skipHours and/or If-Modified-Since

[DamonHD]

Hi,

I appreciate from a scan of the code that doing either would require more state and complexity, but either or both could signficantly reduce bandwidth especially for quiet feeds.

(The are also skipDays and If-None-Match for extra credit, obvs!)

You may need the ability to ignore them on broken feeds, eg with bad Expires/Cache-Control.

Rgds

Damon