[ADD] slides gallery module

- Task: https://www.odoo.com/web?#id=9093&view_type=form&model=project.task
- Pad: https://pad.odoo.com/p/r.QlQTvBv6mCcMrK4B
@tde-banana-odoo How to enable full-text indexation on a column? Only with index=True, or something else? (I'm not sure about that)