Initial pricing component and bundle

Conflicts:
	app/AppKernel.php
	src/Sylius/Bundle/CoreBundle/Resources/config/app/sylius.yml
	src/Sylius/Bundle/PromotionBundle/DependencyInjection/Compiler/RegisterPromotionActionsPass.php
	src/Sylius/Component/Promotion/Checker/PromotionEligibilityChecker.php
	src/Sylius/Component/Promotion/spec/Sylius/Component/Promotion/Checker/PromotionEligibilityCheckerSpec.php
Update registry class and interface references
Spec the group based calculator
Update composer.jsons and travis configuration