HTTP Purge support for (fastcgi|proxy)_cache

[Johan Bergström]

Hey guys (and girls)

We're using fastcgi_cache/proxy_cache quite extensively at our sites,  
and are in dire need of purging content from our cache. Explicit files  
will do in our case, but I clearly see the point of wildcards. The  
only config option I can think of (except modifying parts related to  
proxy_cache and fastcgi_cache such as proxy_cache_methods) is some  
kind of "allow_purge" ACL that is similar to the allow-directive  
already found in Nginx.

We can offer funding for such a feature if feasible assuming this is  
open sourced and preferably ends up in upstream if Igor sees fit.  
Please contact me off list for further discussion if you're interested!

Thanks,
Johan Bergström