MEDIUM: http-ana: Use the version of the opposite side for internal messages

MEDIUM: http-ana: Use the version of the opposite side for internal messages

When the response is send by HAProxy, from a applet or for the analyzers,
The request version is used for the response. The main reason is that there
is not real version for the response when this happens. "HTTP/1.1" is used,
but it is in fact just an HTX response. So the version of the request is
used.

In the same manner, when the request is sent from an applet (httpclient),
the response version is used, once available.

The purpose of this change is to return the most accurate version from the
user point of view.