[ADD] website_forum_seo: adding new module for improving quality of foru...

...m questions and answers.

- Task: https://www.odoo.com/web?debug=#id=9107&view_type=form&model=project.task
- Pad: https://pad.odoo.com/p/r.aAXbFLdZvu62soZi
The help is not helping. Probably something like "Optional URL. The keyword will be replaced by a link to the URL if set" is already a bit more helping.