feat(cc-check-box): add optional required attribute
refactor(directives): renamed file and folder prefixes to sofa
refactor(sofa-full-page-view): CSS adjustments
refactor(styles): huge refactoring
feat(sofa-go-back-control): added new directive

makes ccGo* directives obsolete.
feat(sofa-loading-spinner): refactored directive
feat(checkout-service): added DI for storage and user services
feat(styling): removed general scss files
chore(*): added dist files