* Add new components for ProductCategoryControl, using a reusable SearchListControl
* Add sass variables from wc-admin
* Finish styling
* Save selected categories as selected for the block
* Style sidebar version of control
* Filter the categories list, highlight search term in result
* Filter out selected items in the filter list function
* Add spacing in the placeholder, remove unnecessary stylesheet
* Add a more descriptive label for screen readers
* Remove category references from list item options
* Switch to a configurable object of messages, so SearchListControl can be more customizable
* Add screen-reader message for toggling “done” and moving into preview
* Remove call to getProductCategoryControl
The component is simple enough to just drop in now :)
* Add documentation for all props
* Add padding to placeholder
* Rename fallbackrenderItem to defaultRenderItem
* Add a variable to save the selected count
* Add `isDestructive` to make link red
* Update item style
* Add a hover/focus background color