DD-91 : WIP : Refactor code testing the validity of a drag, drop or paste of a folder or item in the marketplace

DD-103 : Use the same logic than Drag and Drop for Paste operations. Prompt with dialog instead of tooltip though.

DD-91 : WIP : Fix taking the correct root folder (merchant outbox or marketplace listings) into account

DD-91, DD-84 : WIP : Verify restrictions when moving things to marketplace, provide clear alert for errors, parametrize alerts and tooltips correctly

DD-102 : Fix crash when emptying trash containing nested folders. Also avoid getting listings several times

DD-76, DD-77, DD-90 : recycled can_move_to_outbox() into can_move_to_marketplace() so we have now the same logic for both marketplace and merchant outbox

DD-89 : Separate warnings from infos in the SLM API log. Infos are controled by a setting. Warning are always logged.

DD-89 : Add a MarketplaceListingsLogging setting to get SLM API logs. DD-22 : Fixed the delete /listing route

DD-22 : WIP : Implement the GET /listing/:listing route to complete the SLM API coverage. Will be used only in test.

DD-22 : WIP : Implement deleteSLMListing() to cover the Delete /listing/:listing_id route. Avoid recursive calls in deleteListing()

DD-22 : WIP : Cleanep up the class definition, seting methods private and better isolate calls leading to HTTP requests

DD-22 : WIP : Completed the associate_listing route, take edit_url into account and rewrite getListingURL()

DD-22 : WIP : Implement the modify listing route. Made the code more readable and cleared old debug code

DD-22 : WIP : Completed GET and POST listings routes. Refactored the marketplace data code a bit as a result

DD-22 : WIP : Post listing using json, get listings using json (parsing commented out though as too risky and ugly)

DD-81 : Fixed the stock folder count update using an inventory observer. This observe other changes as well of interest to marketplace and should improve consistency in general

DD-73 : Rewrote the move single item to marketplace code so to support the required folder structure better

DD-22 : WIP : Implemented SLM API GET merchant, use it in initialization but glitch in UI (needs to reopen the floater to see content)

DD-58 : Forced listing ID to be an integer throughout. Verify we get an integer when using the associate UI.

DD-68 : Suppress the listing if a listing folder is dragged outside the marketplace back into the inventory

DD-71 : Implement a new item properties floater, calls the same code as the sidepanel in the inventory but with the back button hidden