Misc enhancements

- added getdata.php server page to serve data
- moved model data out of controllers.js into getdata.php
- converted SubTotal function to a service so it can be general use
- moved CSS out of list.html view into its own file (style1.css)
- changed controllers.js to get data from getdata.php
- removed Total function, now using SubTotal + Shipping in view
- detail.html routing now uses item IDs instead of array indexes
- cleaned-up comments