We can't use erb in Ember CLI (since it does not have Ruby) so this has
been ported to use our `javascript:update_constants` rake test instead.
Note we don't have to run this every time a notification type as it's
only used by fixtures to fill in some specific types we test against.
This is where they should be as far as ember is concerned. Note this is
a huge commit and we should be really careful everything continues to
work properly.