Documentation needs more information about the "quickbuild nompi" option

[mjs2369]

Our SIParCS students ran into the same issue when building and running lorenz_63 with DART for the first time. This was that they tried to run filter after running "quickbuild.sh" without having an MPI library available on their local machines, so it failed.

The way to fix this is to simply add "nompi" to the quickbuild command, but this was not apparent to our students working off our guide to compiling DART (https://docs.dart.ucar.edu/en/latest/guide/compiling-dart.html), which makes no mention of it.

While the option is discussed in the "quick-start" section of the home page ([https://docs.dart.ucar.edu/en/latest/README.html#quick-start]
(https://docs.dart.ucar.edu/en/latest/README.html#quick-start)), it can easily be missed here.

edit README.html is now index.html
https://docs.dart.ucar.edu/en/latest/index.html#quick-start

This will be a really simple documentation fix that will add some basic information on how to use the "quickbuild nompi" option to the pages that are needing it:
https://docs.dart.ucar.edu/en/latest/guide/compiling-dart.html
https://docs.dart.ucar.edu/en/latest/guide/quickbuild.html#dart-build-system

This will just make this option a little more obvious to our users, especially those building DART for the first time.

Using DART v10.7.3

[hkershaw-brown]

@c-merchant how is this going? Ready for a pull request?