[payum][paypal] add suppor of instant notifactions.
fix comments.
fix notify order action class.
Use ResourceDataTransformer

and redude hard dependency
Fix lack of caching in SettingsManager

Currently the SettingsManager does not cache resolved settings,
so multiple requests for settings of the same namespace lead to redundant queries and processing overhead.
Add FreeProduct promotion
Add FreeProductAction specs
Rename promotion and fix feedbacks
Fix typo during rebase
Use new DataTransformer
Add translation
Use VariantRepository to reduce SQL queries
Fix TaxonomyRuleChecker

Items in cart are not inventory units
fix sync request not supported.
Implement revert method
Merge pull request #852 from Richtermeister/fix-settings-cache

Fix lack of caching in SettingsManager
[InstallerBundle] Don't use deprecated code
Rework the shipments UI and add datepicker
Add translations
Make the form smaller