response: call transformation directly in http_response_handler
response: call transformation directly in http_response_handler

This removes copy_headers_processed, which wasn't very useful anyway:
the processor will discard most of the headers anyway, and the filters
don't care.

The main intention of this patch was eliminating the head
parser/dumper, which wasted a lot of CPU and memory.


CM4all/beng-proxy,CM4all/beng-proxy,CM4all/beng-proxy,CM4all/beng-proxy,CM4all/beng-proxy,CM4all/beng-proxy