This adds a new script tools/check-version-history.py and a corresponding
test when building in developer mode. It checks manpages (except dbus
documentation which is handled by update-dbus-docs) for missing version
history information.
It also adds ignore lists based on version 183 (the version that our version
annotations go back to). These can be augmented if we want to ignore other
elements if it doesn't make sense for them to have version annotations.
