Getting Started guide: ember v1.3 review

I went threw the Getting Started guide and made sure that all the code works with ember v1.3.
There were some formatting changes like:

- Adding commas to properties in controller
- Keeping tab widths to 2 spaces
- Indicating more clearly that there are more than one properties in `actions` property for a controller
- Indicating more clearly that there are more than one properties for a controller