[NEW] auto-disabling of stateless reply forwarding
I just commited a new functionality in OpenSIPS that will make it more
safe in operation.
The idea is simple: if you do not statelessly forward any request (via
forward() function), the core will also not forward any stateless reply.
This is automatically detected (by inspecting the script and looking for
stateless fwd functions), so you do not have to change anything in the
cfg in order to enable it.
Most of the scripts are stateful (using only TM to forward requests), so
there are no stateless replies to forward -> OpenSIPS will protect
itself (and refuse to become a reply relay) and drop all stateless replies.