product collections
Merge branch 'master' of https://github.com/songecko/piga-ecommerce.git

Conflicts:
	app/config/sylius.yml
	src/Gecko/PigalleBundle/Repository/ProductCollectionRepository.php
	src/Gecko/PigalleBundle/Resources/config/doctrine/ProductCollection.orm.yml
	src/Gecko/PigalleBundle/Resources/config/doctrine/ProductCollectionImage.orm.yml
	src/Gecko/SyliusBackendBundle/Resources/views/ProductCollection/Form/_images.html.twig
	src/Gecko/SyliusBackendBundle/Resources/views/ProductCollection/Form/_main.html.twig
	src/Gecko/SyliusBackendBundle/Resources/views/ProductCollection/index.html.twig
	src/Gecko/SyliusBackendBundle/Resources/views/ProductCollection/list.html.twig
	src/Gecko/SyliusBackendBundle/Resources/views/ProductCollection/show.html.twig
	src/Gecko/SyliusBackendBundle/Resources/views/ProductCollection/update.html.twig