[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
Please see all comments on this method. Basically you should rewrite it cleanly
 - manage your inputs (category, tag, search criterions)
 - manage the pager
 - manage the data to fetch
- prepare the final values and render the template