NAT: warnings.
NAT/bsd: returns original number of preallocated 16kb mbufs.
scm cleanup
NAT: increases jumbo16 zone. TSO/SGO heavily uses jumbo16 in case of p2p or some UDP benchmarks (e.g. namebench), eating current limit too fast.
NAT: excludes BSD functions, which might confuse reader.
NAT: BSD mbufs zones allocated at the moment when the number of elements is known. sub-zones don't allocate but borrow slices from master zones.
OSE fixes for NAT