Tests pass with ember 1.0.0-pre4.

Also, explicitly testing support for translations that use helpers.  Note that
these helpers must be registered with `Handlebars`, not `Ember.Handlebars`.
This means bound helpers aren't supported.
Merge pull request #36 from hjdivad/ember-1.0.0pre4

Tests pass with ember 1.0.0-pre4.