Split big universal RNG into view-specific schemas and moved rng based view validation
into view_validation.py file.
Adapt old views, and remove deprecated tag `version="7.0"` from views.
Since the previous commit, the `color_field` needs to be explicitly stated
in the options for the tags to be colored.
The previous behaviour (always read the field `color`) was leading to server
warnings if the field was not present on the comodel.
Thìs commit set the `color_field´ for every many2many_tags on fields that have
a `color` field on the comodel.
In f65475d6 one2many fields of default view in a form view were propagated
to the ORM so the value received from an onchange was not empty.
These new steps test this on a tree view embedded in a form view, or a
tree view originating from a default view by testing onchange adding row
or updating values of a one2many.
Mitali Patel