Adding Ember

This adds ember to the generator.

For javascript concatenation and dependency management, [grunt-neuter](https://github.com/dylang/grunt-neuter) is used.

Handlebars templates are stored in `source/templates` and are precompiled with [grunt-ember-templates](https://github.com/dgeb/grunt-ember-templates).

Right now, the external libs are added to the page in script tags, but we could consider adding them to the `grunt neuter` task for concatenation.