disable submissions page when no exam is selected
Closes #227 (closed)
Note that we need to do better than this to solve #226, as each page should sensibly display an error message if its props are not set in a a sane way
Closes #227 (closed)
Note that we need to do better than this to solve #226, as each page should sensibly display an error message if its props are not set in a a sane way