Here listed all api breaking changes.
When something changes capable of breaking things NFQWS2_COMPAT_VER increases.

v2
* removed "stun_binding_req" specialized payload. replaced with common "stun" - any stun packets, not only binding request.
every LUA relying on desync.l7payload should be revised.
nfqws2 --payload option and init.d custom scripts must be updated.
