SOLM12 — Specification should not be tied to XTCE and GEMS terms

The terms XTCE and GEMS should not be part of the SOLM meta models or functions that are projected from it (like SpacePython).

The specification should talk about Parameters that are being queried (possibly as Spacecraft or Ground Parameters), though the transport/method should be decoupled since there are multiple interfaces that could be used (direct integration with an end product, via GEMS, via SNMP, via a message bus/C2MS, or perhaps via a database).

Addressing references to the PSM of SpacePython at this time

The updated section of SpacePython (section 8) is being replaced with new content as part of issue #6. The updated version addresses this issue for the single PSM that remains as part of SOLM.