Add empty tests for adapter and serializer.

I played around with trying to get the tests working but I couldn't figure it out.  I'll add some comments inline.
@benkonrath that seems strange.  I will have to take time this weekend to fully explore what's going on here, but try taking a look at https://github.com/huafu/ember-data-sails.  Their addon is not the same thing as what we're building, but maybe we can learn good testing practices from them.