Document data visibility rules for events/objects/attributes

[Wachizungu]

Might be useful to document this, if someone can confirm my understanding is correct I'll add it.

As I understand it the rules are the following, you can see an event/object/attribute if:

• You are a site admin
• You have any of the other roles and one of the below statements are true:
  • You belong to the owner org of the event and the distribution is 'Your organisation only'
  • The distribution of the event/object/attribute is 'This community only', 'Connected communities' or 'All communities'
  • You belong to the sharing group of the event/object/attribute

On sync, if the distribution was a sharing group and the syncing user's org is not in the sharing group, it will be added.