Standardize the aeropropulsive scenario and add an example

[anilyil]

The aeropropulsive scenario is currently only used for my benchmark optimization study. Once that is finalized and released, we should put a simplified version in mphys and possibly clean up the aeropropulsive scenario definition.

[kejacobson]

• Add standardized AeropropulsiveScenario to MPhys library
• Add Documentation of Aeropropulsive scenario
• Add open-source podded fan benchmark case (ADflow + pyCycle)
• Simple example using pyCycle in MPhys. CFD inputs can come from an IVC and run a feed-forward explicit analysis