ENH: Store orbital elements as a dict

[jklenzing]

Is your feature request related to a problem? Please describe.
missions_sgp4 has a lot of kwargs, some of which are mutually exclusive.

Describe the solution you'd like
We could expand the element checks in the orbital methods to store these as a single dict for input, similar to how pysat treats "orbit_info". Could reduce duplication if new instruments are added down the line.

Describe alternatives you've considered
Rely on the docstrings in the instrument to sort it our.

Additional context
thoughts from codeclimate review (too many kwargs in load)