[http] improves client side caching support for GET requests on static files.
[plugins] director: explicitely set content-length response header on cached results (as we know it in advance)
[http] HttpRequest: extends API to allow explicit removal of certain request headers (useful if you do not want to propagate conditional gets or connection-level request headers to some origin server
[plugins] director: support client-side caching
TODO-list update (ideas ideas ideas)
documentation fixes
[x0d] fixes main function 'autoindex' not respecting the first item in list
update
update
rename cmake var: {X0,ENABLE}_DIRECTOR_CACHE