[Users] NEW FUNCTIONALITY: add_rr_param() in BRANCH / FAILURE routes

Hi, the add_rr_param() can be new safely called from BRANCH / FAILURE routes. The behaviour will be: - in BRANCH route - the RR parameters are set only for the current branch, so you can have different RR params for each branch - in FAILURE route - the RR parameters will be set only for the outgoing branch, so during serial forking you may add additional RR param function of the new destination. Additional improvements in the RR module usage: -record_route() may take as parameter a string to be appended as RR param; pseudo-variables may be used. -add_rr_param() and record_route_preset() accepts pseudo_variables in parameter. Here is a short example on what can be done with the new functionality: { ..... record_route(";param1=xxx"); t_on_branch("1"); t_on_failure("1"); ..... t_relay(); } branch_route[1] { add_rr_param(";param2=yyy"); ....... } failure_route[1] { add_rr_param(";param3=zzz"); t_on_branch("0"); #reset append_branch( URI_2 ); t_relay(); } The output will look like: after first relay: ";param1=xxx;param2=yyy" after failure route relay : ";param1=xxx;param3=zzz" regards, bogdan