directives to set value, rather than append values to headers, env
setenv.set-request-header
setenv.set-response-header
setenv.set-environment
These directives take precedence over the setenv.add-* counterparts
Set a blank value for request or response header to remove the header
(blank value in environment will be set as the value; not removed)
setenv.*-environment is now deferred to handle_request_env hook.
setenv.*-response-header is now processed in handle_response_start hook.
x-ref:
"setenv.add-or-replace-response-header"
https://redmine.lighttpd.net/issues/650
"set-request-header or remove-request-header support for mod_setenv"
https://redmine.lighttpd.net/issues/2295
Glenn Strauss
Elan Ruusamäe
Jan Kneschke