Optional group name

[Raruto]

Checklist

• [x] I've searched through the current issues to make sure this feature hasn't been requested already.

Motivation

Similar to: https://github.com/g3w-suite/g3w-admin/issues/498

When creating a new group, the only field really needed is its SRID:

Suggested solution

Use SRID number of the group as a fallback for the title and name fields when not specified (as in the image above).

Alternatives considered

Maybe related to: https://github.com/g3w-suite/g3w-admin/pull/567

Somehow related to: https://github.com/g3w-suite/g3w-admin/issues/552