[ADD] website_banner module

- Task: https://www.odoo.com/web/#id=9562&view_type=form&model=project.task
- Pad: https://pad.odoo.com/p/r.z6vfT0m2KIjzoY3f
hello @vme-odoo  , it's not For Drag and drop issue but on Edit mode of website We need to off the mouseleave event  of the document  and when we drag and drop snippet editable_mode is true(it's fine) but when Just Click On "Edit" buttton we can not able to get the editable_mode True so need to check  isContentEditable.