New page to document the new features of the demo payment provider, and
modifications to related pages
task id: 2982367
closesodoo/documentation#3088
X-original-commit: a1f4c3704b
Signed-off-by: Castillo Jonathan (jcs) <jcs@odoo.com>
Signed-off-by: Aarab Tom (toaa) <toaa@odoo.com>
