Quick way to instantly propose correction on a resource content

[bkis]

1. Add a widget to the resources in browse view (only visible if logged in!): Edit icon
2. Click opens modal with a textarea for a correction proposal (and a short info text on what is happening!)
3. Process the correction:
   • Option A (very simple): Correction is sent as a user message to the responsible user / admins
   • Option B (better but tricky): Correction goes to an extra corrections collection, references the content in question; responsible user / admins are notified; correction is shown to the responsible user in browse view and content view

[bkis]

This would go perfectly hand in hand with #254