Add functionality for 'analysis' modes that do not involve mission trajectory optimization

Desired capability or behavior.

There are lots of examples where an aircraft designer might only want to use the relationships inside aviary and not perform an entire Aircraft / Mission Optimization.
These might involve:

• Simple Takeoff & Landing
• Mass Breakdown
• Aerodynamic Analysis

It could be useful for someone looking at sensitivities of the Aviary relationships to input variables, where an entire aircraft or mission analysis is not required.

We could add a flag into the input file to toggle these things without providing a phase_info, and/or potentially add additional functions to the CLI.

Suggested implementation.

The unittests for Takeoff, Landing, Aero and Mass estimations might be a good place to start by checking how those test problems are setup.
These could form the basis for examples showing this analysis behavior or a variable toggle to setup the problems in the correct way without running a trajectory optimization.

Start with the unit tests for Takeoff, Landing, Aero, and Mass estimations, as suggested in the issue, and inspect how those test problems are set up. Determine how an input-file flag or CLI option could run these analyses without phase_info or trajectory optimization; done means the supported analysis modes can run independently and are covered by examples or tests.