Merge pull request #1085 from intportg/APIWeb

Refactor order process frontoffice code to reuse parts of it in return p...
Fix context on WEB API
Fix cart directive
Merge pull request #1086 from inthause/APIWeb

Fix context on WEB API
Fix credit notes amount in CartDataComposer and OrderDataComposer (there is no tax notion here).
Add notifications on product returns + refactor commerce notifications + fixes.