This was a workaround to be able to build on case-insensitive file
systems where it might get confused about <string.h> vs <String.h>.
Let's just not support building that way, so String.h can have an
objectively nicer name. :^)
This way, CNotifier can mutate state to its little heart's content
without destroying the world when the global CNotifier hash changes
during delivery.
