Make headers (especially of raw data) fully reproducible

The FITS headers should be fully reproducible.

Therefore they should contain

• Version numbers of MicadoWISE, ScopeSIM and anything else that is relevant. (Perhaps just of MicadoWISE if we pin every dependency?)
• Random seed used by ScopeSim, !293 (merged), but should check
• Process parameters. These should be there already.