[MEDIUM] http: make the request filter loop check for optional conditions

From now on, if request filters have ACLs defined, these ACLs will be
evaluated to condition the filter. This will be used to conditionally
remove/rewrite headers based on ACLs.
diff --git a/include/proto/proto_http.h b/include/proto/proto_http.h
index cfaf985..6a424c0 100644
--- a/include/proto/proto_http.h
+++ b/include/proto/proto_http.h
@@ -75,7 +75,7 @@
 void get_srv_from_appsession(struct session *t, const char *begin, int len);
 int apply_filter_to_req_headers(struct session *t, struct buffer *req, struct hdr_exp *exp);
 int apply_filter_to_req_line(struct session *t, struct buffer *req, struct hdr_exp *exp);
-int apply_filters_to_request(struct session *t, struct buffer *req, struct hdr_exp *exp);
+int apply_filters_to_request(struct session *s, struct buffer *req, struct proxy *px);
 int apply_filters_to_response(struct session *t, struct buffer *rtr, struct hdr_exp *exp);
 void manage_client_side_appsession(struct session *t, const char *buf, int len);
 void manage_client_side_cookies(struct session *t, struct buffer *req);