Point to the editor URL
Unified units query
Singularize permission checking

Views only check a single permission at a time.
Oops, wrong permissions being checked
Added project-centric `view` permissions

  - `view` permissions set at the project-level (or, as a fall-back, at
    the root directory) will be taken into account when determining the
    visibility of projects or translation projects.
  - Editing operations that span multiple languages/projects will only
    display the units contained in the set of projects accessible by the
    current user.

Fixes #3.