* Add placeholder image for product preview
This adds the designated placeholder image url from settings into the
wcSettings global for the blocks to use. Then uses the placeholder url
when a product doesn't have any images.
* Updated based on review notes
Using `$block_settings` instead of `$settings`
Using '' alt tag
Updated snapshot
* Add the placeholder global to test that it passes through to the preview
* Add products by attributes tests
* Add new properties to Products endpoint args
Allows for requesting a combination of attribute terms across different attributes.
* Unskip working tests
* Included PHPCS and git hooks
* Fixed coding standards
* New Products endpoint
* Fixed product controller schema
* Improved products controller schema and response
* New product categories controller
* Updated REST API base to match WooCommerce authentication
* Fixed products/categories endpoint
* Better docblock
* Product attributes controller
* Product attribute terms controller
* Update REST API urls
* Reverted PHPCS changes
* Check permission only once while fetching posts
* Included raw price
* Included sku to products endpoint response
* Fixed endpoints in unit test
* Fixed routes in unit tests
* Check and use subscriber, contributor and author rules in unit tests
* Add travis to run JS & CSS linting, JS tests, and PHPUnit tests
* Move API initiation out of the gutenberg/files check
So that php tests run without having to build the JS files
* Add very basic product endpoint tests
* Fix stylelint issues in CSS
* Remove e2e setup, replace with dependency setup
* Add missing install step
* Remove cache for now
* Add specific `har-validator` dependency because v 5.1.2 has disappeared
* Only run npm install for the JS test job
* Check for installed plugins
* Update install location
* Fix typo in plugin name
* Check the BRANCH variable, rather than TRAVIS_PULL_REQUEST_BRANCH, which is only set on PR runs
* Remove debug command
* A change to trigger CI
* Set the expected node & npm versions
* Remove copy-pasted command, does not apply