Downgrade backend request/response to HTTP/1.0

[Dave Pascoe]

Is there a way in haproxy 1.4 to perform the equivalent function that
these Apache directives perform?

 SetEnv downgrade-1.0 1
 SetEnv force-response-1.0 1

i.e., force haproxy to downgrade to HTTP/1.0 even though the client is
HTTP/1.1

TIA,
Dave