Keep an option in the future to create accounts without permission to see annotations by others

[jgonggrijp]

Right now, we have a permission that controls whether a user can see annotations made by other users. This was originally envisioned as a temporary measure, to facilitate early annotation campaigns that were meant to assess inter-annotator reliability (see #242). Indeed, the intention is still that all annotations will be visible to the wide public, as confirmed again today by Brigitte Ouvry-Vial. In the future, regular users should be able to control for themselves whether they see annotations from other people (see #179, #180, #255).

There will, however, remain a use case for creating accounts that cannot see annotations by other users, as remarked today by Michael Wögerbauer. One possible way to address this is to keep the permission, but add it to every new account by default. In order to create accounts without the permission, we could employ either or both of the following options:

• Enable staff members to create a special invitation link, which when used, creates an account without the permission. It should be possible to send one such link to multiple people at the same time. An interesting extra option for this approach would be to automatically add all users who followed the invitation link to a particular group as well.
• Ask new users who sign up the regular way which situation best describes them: annotator contributing to a research project, general interest or researcher. This choice will then inform which permissions they receive initially: respectively none, only seeing annotations by other users, or seeing annotations by other users and uploading sources.

There are probably more options. I suggest that we form a well-educated opinion on this and then discuss with the consortium before making a final decision.

[jgonggrijp]

In the meanwhile, partly because of #503, my own opinion has evolved as follows. Since preannotations and annotations by other users are hidden by default and we can probably trust (and instruct) future annotation campaigners to not turn them on, I don't think any measure to enforce this will be needed any time soon. That amounts to the following, simpler option:

• Remove the need for a permission to see annotations by others, as well as the permission itself. Keep a tag to the commit in which we removed the feature and preserve the general mechanism for establishing triple store privileges. In the unlikely future event that we actually want a hard way to prevent people from seeing annotations by others, introduce a "reverse privilege" based on, but opposite to, the original privilege (i.e., you can only see annotations by others if you don't have it). This "antiprivilege" can then be added to users after they have created their accounts, but before they start annotating.