Update for ember.js 1.3/ember-data 1.0-beta6

1. Update ember.js to 1.3.0, ember-data to 1.0.0-beta6, handlebars to
1.1.2
2. Change application.hbs
{{partial navbar}}
to
{{partial 'navbar'}}
to make it work properly.  Seems new handlebars no longer allow the old
way of doing partial.
3. Update webapi.client and EntityFramework packages to the one shipped
with VS2012 update 2
4. move todos normalizeHash to todo serializer, as ember data changes
5. todo.saveCheckbox should not check the isDirty attribute as this
version of ember data