Lets assume most people don't have curl installed on the system path for the notice url pings.
NGIN-13: Added code to detect the VAST tag type from local demand partners as XML or a VAST URL to pull down XML.
I added this because so many ad networks wanted to use the Demand Dashboard with LiveRail and other video rev-shares.
In that case it will reverse proxy the VAST XML down from the LiveRail or whatever, and forward that to the publisher's video player. In doing that it will trigger the stats in the LiveRail, ect... dashboard, so your numbers aren't off. The new optional caching flag for rev-share VAST urls will optionally cache the LiveRail VAST XML pulled down from the URL, except if you do that it may throw your numbers off on the rev-share video server so I left it as an optional flag in the config turned off by default - cache_proxied_vast_xml in delivery.local.php