ERP5 Base: Refactor addition of new objects for erp5 objects

It's better to create new objects using same script rather than
keeping 2 scripts that try to do the same thing: Folder_create
(script used to add in case we create new object using the icon next to actions bar)
did not support the getRedirectParameter API. We now do all the work
related to adding new object in Folder_create itself.