BUG/MINOR: http-rules: Replace path and query-string in "replace-path" action

BUG/MINOR: http-rules: Replace path and query-string in "replace-path" action

The documentation stated the "replace-path" action replaces the path, including
the query-string if any is present. But in the code, only the path is
replaced. The query-string is preserved. So, now, instead of relying on the same
action code than "set-uri" action (1), a new action code (4) is used for
"replace-path" action. In http_req_replace_stline() function, when the action
code is 4, we call http_replace_req_path() setting the last argument (with_qs)
to 1. This way, the query-string is not skipped but included to the path to be
replaced.

This patch relies on the commit b8ce505c6 ("MINOR: http-htx: Add an option to
eval query-string when the path is replaced"). Both must be backported as far as
2.0. It should fix the issue #829.