Eng 6245 Add support for applying a binary changelog

The fact that we have a "normal" pathway here that is big endian and a DR pathway that's LE kind of brings back around a rather silly question: if in general we expect everything to be BE except a couple of special pathways, maybe the unqualified versions of SerializeInput et al. should be typedefs of the BE specializations? On second thought, that's probably going to do more harm than good. Large number of changes or no, LE and BE suffixes on everything at least make what's going on clear.