Part 5: Add table of x-ogc- properties

[m-mohr]

I think it would be valuable to add a table of all the pre-defined additions to JSON Schema, i.e. with the x-ogc- prefix.
It would help to understand schemas more easily, especially as some schemas consist of more proprietary properties than JSON Schema vocabulary.

PS: Generally, it feels like the number of additions to JSON Schema is a bit excessive.

[pvretano]

SWG Meeting 29-JUL-2024: Yes, all present agreeds that a table of x-ogc- values would be useful. @pvretano will add.