Refactor API.
Change input placeholder text.
Correct comments.
Merge pull request #1 from jDeppen/api

Refactor API to remove duplication and add UPC.
Create groupings by UPC. Create basic filtering.
Merge pull request #3 from jDeppen/orderBy

Create groupings by UPC. Create basic filtering.
Enable grouping options, ordering groups by group key
Enable custom ordering and filtering at group level.
Add links to product items.
Merge pull request #5 from drabinowitz/filteringOptions

Enable custom groupings, custom orders, and product links.
Remove .DS_Store.