Add section describing existing filtering points. Document byteorder behavior in AF_INET[6] hooks in new section.
Add section describing existing filtering points.
Document byteorder behavior in AF_INET[6] hooks in new section.

MFC after:	2 weeks

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase