REST API: nested item.category and order.invoice for ease of access in delivery bucket
Add remove button to filter, and display filter value.
Merge pull request #61 from this-username-is-taken/rest_api

REST API: nested item.category and order.invoice for ease of access in delivery bucket
Add searched item not found message.
Merge pull request #62 from gregwym/filter

Add remove button to filter, and display filter value.
Merge pull request #63 from gregwym/no-result

Add searched item not found message.
Changed tabs from 4 spaces to 2 spaces
Added filtering by time, e.g. /api/delivery_bucket/?after=2014-03-17