In an effort to prevent the user from reaching a state that would result in an error (and just a general better UX overall), we should disable the headerRight 'Create' button when the role name is empty. We should allow a user to create a role without any selected permissions because on the keyserver, we add a set of guaranteed permissions anyways, so we won't end up with a case of a role with no permissions.
Error handling for duplicate role names / etc will be done in a later diff.
Part of ENG-4178
Depends on D8428