Bug fixes

fix core_version_requirement

Hightlights

Events
We have added the possibility for Inviting users to an Event, also users that are not yet member of a platform.
We have added the possibility for users to be able to request enrollment to an Event

Groups
We have added the possibility for Inviting users to a Group, also users that are not yet member of a platform.
We have added the possibility for users to be able to request becoming a member of a Group

Fixed a bug with multiple rendering of the same content.

Fixed issues: