[IMP] website: unable/enable snippet options for some snippets (parts)
[IMP] website: unable/enable snippet options for some snippets (parts)

* Remove background position and color options for parallax
* Add background/color options for .jumbotron (button and big message)
* Add background/color options for s_cover and s_banner text container

ygol/odoo,dfang/odoo,ygol/odoo,ygol/odoo,hip-odoo/odoo,dfang/odoo,hip-odoo/odoo,ygol/odoo,ygol/odoo,dfang/odoo,hip-odoo/odoo,dfang/odoo,hip-odoo/odoo,dfang/odoo,hip-odoo/odoo,hip-odoo/odoo,dfang/odoo,ygol/odoo,ygol/odoo