feat: Added datadoc and list access permissions for user groups

[jij1949]

This PR takes the already implemented user groups and expands them so that they actually grant permissions to their members. These user groups can be assigned as editors for datadocs or lists, and can have read or write privileges. Groups can also be members of other groups, and therefore groups can also inherit permissions from other groups which they will then pass on to their members.

In addition, a user will always have the access level of its most permissive permission. For example, if a user is directly added to a datadoc with read-only permissions but is also a member of a group with edit permissions, the user will have edit permissions until the group is removed or the group permissions revoked.

[czgu]

wow this is awesome!

[jczhong84]

lgtm. @jij1949 thanks for the updates! could you resolve the conflicts?

@czgu do you have any other comments or concern of this feature?