users and groups:
* No: Every user can invite other users and groups (default and old
behavior)
* Groups: other users can allways be invited, only groups require an invite_grant
* Users + groups: inviting both allways requires an invite grant
One need to keep in mind, that setting an invitation ACL via a group,
gives each groupmember the right to invite the group / create a group
event. So the last option propable only works, if users manage
invitations grants on their own, or admin only sets it in small working
groups, where every member is allowed to invite the whole group.
--> calendar backend code removes participants a user is not allowed
to invite
- new "only groupevents" filter, showing only real groupenvents not
events of groupmembers (added tooltips to explain filters)
If an entry which is opened by another user, gets saved by another user before the former commits its changes, the former user is notified at the
time saving the event and asked to reload the event and reedit. A link to reedit is provided.
Additionally there is a feature to inform a user that a given entry is opened by another user within a configurable timespan.
This feature was developed by Stefan Becker
