Better onboarding on demo instance

[fm3]

Lots of improvements for new users on webknossos.org:

• Signup on frontpage
• 1 organization per new user
• Public Datasets hidden in list (only on demo)
• Show featured publications in dashboard
• New user banner with information
• Better welcome email
• Improved info tab in annotation view
• Renamed tracing -> annotation
• Improved docs
• Refactored DatasetCache from Dashboard in own component with context

---

• Updated changelog
• [ ] Updated migration guide if applicable
• Updated documentation if applicable
• [ ] Adapted wk-connect if datastore API changes
• [ ] Needs datastore update after deployment
• Ready for review

[fm3]

@normanrz I added the organizationDisplayName to the query as specified. if organization is emptystring, the backend will use a normalized version of organizationDisplayName for the name.
Also, I added /organizations/:organizationName as you requested as well as restricting /organizations so that it will fail if there are multiple organizations on the server. I did not yet adapt the frontend to those changes (except for setting some values to default values so that the requests don’t fail)

[normanrz]

@fm3 For deployments with a single org, can we have a route like /api/organizations/default that returns the single org?

Also, the "organziation team" uses the cryptic org name, can we change that to something more generic like "Default"?

[philippotto]

What's the status here?

[normanrz]

I think the code should be ready, but I need to do one more round of checking.

[fm3]

I didn’t do the frontend changes for switching to /organizations/default, I guess those are still to do?

[philippotto]

@fm3 I just merged the master into this PR and resolved most of the conflicts. However, there are still conflicts in app/controllers/Authentication.scala which I didn't feel comfortable to resolve. Could you have a look at these if you have a minute? :)

[philippotto]

@fm3 Sorry to bug you again, but the getDefaultOrganization route returns an error message (à la "cannot list organizations due to privacy reasons"), but the front-end cannot know whether this is an multi-orga setup or not (at least, I don't think so). Could you just return null if there are multiple organizations?