I use a variety of doxygen versions among the systems
that run the unit tests, including my personal development
systems and GitHub Actions.
Older versions of doxygen complain about options in Doxyfile
they don't know about.
Newer versions of doxygen complain about obsolete options in Doxyfile.
I'm trying to get rid of all these noisy warnings by pruning
all options in Doxyfile that are equivalent to their default
values. I only keep the options that I need to be different
from the default.
Hopefully this quiets down the warnings.
In all 4 supported languages, use consistent constant names for
Earth and Moon radii.
Use Moon's equatorial radius for rise/set timing.
Use Moon's mean radius for calculating Moon's umbra radius for
detecting solar eclipses.
Also use Moon's mean radius for determining whether the Earth's shadow
touches the Moon, for finding lunar eclipses.
Use the Moon's polar radius for distinguishing between total
and annular eclipses, with a 14 meter bias (instead of 1420 meters!)
to match Espenak data.
Use consistent unit test error threshold of 0.57 minutes for rise/set.
Updated demo test data for slight changes to rise/set prediction times.
Updated doxygen options to issue an error on any warnings.
Fixed the incorrect function name link that doxygen was warning me about.
