Integration of cloudinary media gallery in editor

[Ma-Kas]

Logic:

• Media gallery opens, pick image(s) to drop into editor and lexical state
• Here, they need fully functional url, meaning prepend base URL and transformations
• However, in database, they need to be saved as just the urlSlug
• So, in the imageNode, GalleryNode etc, in the exportJSON functions, extract the urlSlug, to only send that to database
• In importJSON functions, do the opposite again to give editor a fully functional url again when fetching from db