Completing the do_cube_transform implementation in make_hgrid v2.0

[ngs333]

This PR completes the do_cube transform implementation in make_hgrid. The feature was requested in issue #179. Upon code inspection, exploration and testing we determined that only minor code changes were needed to complete its implementation.

This is an important feature which was unfinished and therefore without testing, exercise or coverage in any unit test, and so a reference unit test (# 33) was added. The unit tests compare make_hgrid horiz grids created analyticall vs created from reference FV3 output grid spec files. Additional manual testing was done and further discussion is available in issue #179.

The earlier version of this PR (#194) was closed without merging in order to facilitate complete remove the larger ( approx C128 size) reference files from github.

[ngs333]

The PR was closed to facilitate the complete removal of the very large unit test reference files. There is a replacement PR that uses smaller (C48 size) files #195 which are more convenient.

[ngs333]

Accidentally closed wrong PR. Re-opening.

[bensonr]

@underwoo - do we want any datafiles in our test suite? If not, is there another way to make them available for CI testing within the container?

[lharris4]

Looks good to me. Thanks.

[ngs333]

@underwoo - do we want any datafiles in our test suite? If not, is there another way to make them available for CI testing within the container?

@underwoo , @bensonr
The Test33 reference dataset is six files of 132 KB each. Current size of
the t directory immediately after a git clone is 887 MB.

[ngs333]

@underwoo - do we want any datafiles in our test suite? If not, is there another way to make them available for CI testing within the container?

@underwoo , @bensonr The Test33 reference dataset is six files of 132 KB each. Current size of the t directory immediately after a git clone is 887 MB.

@bensonr @underwoo @ceblanton
Concerning datafiles in our test suite, this perhaps should be theme that is part of the next release (after 2022.02), and I added I added existing issues ( #76 , #51) to the next project.