The Doxygen html generation takes a lot more time than the xml
generation. If all you want from Doxygen is the xml for the user's
guide, that can be frustrating. Add an option to turn off the xml.
This is a start of moving the VTK-m User's Guide into the VTK-m source.
This is only the start of the process. There are several goals of this
work.
1. Integrate the documentation into the source code better to better
keep the code up to date.
2. Move the documentation over to Sphinx so that it can be posted online
and be more easily linked.
3. Incoporate Doxygen into the guide to keep the documentation
consistent.
4. Build the user guide examples as part of the VTK-m CI to catch
compatibility changes quickly.
There are still some warnings left:
* Some text in markdown files are incorrectly picked up as
doxygen commands
* ArrayPortalTransform weirdly inherits from a specialized
version of itself. It's technically correct C++ code, but
gives doxygen fits.
Sandia National Laboratories recently changed management from the
Sandia Corporation to the National Technology & Engineering Solutions
of Sandia, LLC (NTESS). The copyright statements need to be updated
accordingly.
