The releases on the repository can be misleading regarding the status of GeoParquet as an OGC Standard

[doublebyte1]

The releases on this repository refer to the specification, but looking at the way releases are managed in other OGC repositories (e.g.: JSON-FG, OGC API Tiles they can be interpreted as versions of the draft standard.

In this PR, the README is updated to reflect that this is a draft standard and the releases are not releases of the standard.

[cholmes]

Closing this, as there is now language in the main branch of the repo. Let us know if it needs any more adjustment.