adding physical and math BC types for inflow-outflow BCs

[mukul1992]

Summary

This feature would be useful for managing boundaries with both inflow and outflow cells. By adding these types in AMReX, they can be used consistently across various inter-dependent codes such as IAMR, AMReX-Hydro, and AMR-Wind.

Additional background

The ongoing addition of an inflow-outflow BC in AMR-Wind is the primary motivation.

Checklist

The proposed changes:

• fix a bug or incorrect behavior in AMReX
• add new capabilities to AMReX
• changes answers in the test suite to more than roundoff level
• are likely to significantly affect the results of downstream AMReX users
• include documentation in the code and/or rst files, if appropriate