Forward Accept HTTP Header Field

[christianmahnke]

The resolver should forward the HTTP Accept header field [1] to allow the repositories to return certain requested media types, likes images without HTML frame.

[1] http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html

[hwhw]

the Accept header should be re-offered by the user agent after following the redirect, so this should already be possible