Update the policies to allow https://www.opengis.net/def

[ghobona]

Several websites and browsers now prevent access to resources on http from https.

This has come up in a previous OGC API Virtual Code Sprint.

There is an increasing need to update the OGC-NA policies to allow registration of concepts under https://www.opengis.net/def.

So the proposal is:

1. To update the OGC-NA policies such that after a nominal date (e.g. 30 June 2022) all future item registrations would be under https://www.opengis.net/def instead of http://www.opengis.net/def.
2. Existing registered items under http://www.opengis.net/def would not be modified.
3. Any concepts currently registered under http://www.opengis.net/def, would need to be re-registered as new concepts under https://www.opengis.net/def, and
4. A skos:exactMatch statement would be declared to indicate a high degree of confidence that a concept in https://www.opengis.net/def can be used interchangeably with another in http://www.opengis.net/def.

[ghobona]

Closing this issue because it duplicated another.