When adding a new user to a project in the "Add new team member" section, it's possible to click 'Add' without having selected a user. This will generate an internal server error:
NoMethodError (undefined method each' for nil:NilClass):
app/models/users_project.rb:72:inblock in bulk_import'
each' for nil:NilClass):
This is merely a usability issue since one normally has to select a user, but showing
a error message instead of failing hard would be nicer.