Fixed incorrect surface moment derivatives and added a moment output to the component

[sabakhshi]

Purpose

Adds moment as a directly output from OAS in addition to CM. Fixes bugs related to derivative computation for CM. Adds significant commentary to the derivative code to explain what is going on. Cleans up code.

Expected time until merged

1 week

Type of change

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (non-backwards-compatible fix or feature)
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no API changes)
• Documentation update
• Maintenance update
• Other (please describe)

Testing

Some of the derivative updates need to be checked.

Checklist

• I have run flake8 and black to make sure the Python code adheres to PEP-8 and is consistently formatted
• I have formatted the Fortran code with fprettify or C/C++ code with clang-format as applicable
• I have run unit and regression tests which pass locally with my changes
• I have added new tests that prove my fix is effective or that my feature works
• I have added necessary documentation

[eytanadler]

Thanks @sabakhshi! More comments are always appreciated, particularly in complex derivative routines.

[kanekosh]

Nice catch! I know you're working on it but I'm writing down as a note:
Test setup should be updated to be physically valid and to avoid false positive, which the current test does.

[eytanadler]

One more very minor comment. Could you also update the patch version for now so that we can track which versions have this fix while we wait on the numpy and openmdao update in #450?