Add Data tab to the extension

This is a work in progress to add a `Data` tab to the extension.

Main purpose is to display the defined models in the application, and adds the ability to view and inspect the loaded records for each model type.

- [x] Add a Data tab to the extension which includes model types and records
- [x] Improve search functionality
- [x] Add custom defined filters (checkboxes) next to search
- [x] Allow the adapter to color records based on state or other.
- [x] Add a data debug adapter to Ember core [PR submitted](https://github.com/emberjs/ember.js/pull/3129)
- [ ] Extend the data debug adapter in Ember Data [PR submitted](https://github.com/emberjs/data/pull/1114)
- [x] More test coverage for all of the above
- [x] Design an icon for the data nav item


A model's columns and values are defined by the adapter.  The adapter can choose to add any column, such as state or other information.

Model Types:

![extension_model_types](https://f.cloud.github.com/assets/1061742/939088/b00521a0-010c-11e3-9b1f-2aca375cb4c9.png)


Clicking on a model, will list the available records:

![extension_records](https://f.cloud.github.com/assets/1061742/939090/b954af5a-010c-11e3-9cb7-3551d3e03e11.png)

We can search for a specific record:

![extension_search](https://f.cloud.github.com/assets/1061742/939094/c9ffc254-010c-11e3-93db-b1c2dae19dfd.png)