Export/Import marker as symbol identification code (SIDC)

[Timi007]

Is your feature request related to a problem? Please describe.
It would be nice to export as symbol identification code (SIDC) and also import SIDCs. This would allow for better interoperability between other marker creation applications like Spatial Illusions.

Describe the solution you'd like
Two functions:

1. A function to export an existing marker as SIDC.
2. A function to create a marker with a SIDC. Alternativly, a function returning the required marker parameter from the SIDC which can be directly passed to the existing createMarker function.

Additional context
The SIDC could also be used to export/import presets (#31)