[DOC] doc: add dashboard view documentation
[DOC] doc: add dashboard view documentation

This commit add the reference documentation for the new dashboard view.
In an ideal world, this should be done in the enterprise repository, but
our documentation system is not extensible that way.

ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo