refactor attributes'value generator to deal with yams special
Attribute/NOW/TODAY values that may be used on [Interval]BoundConstraint
(BoundConstraint wasn't handled btw, fix this).
Besides passing 'entity' to generate_* function (needed to get value for
another attribute when computing one for instance):
* set nicer method names and makes clearer what's private/protected/public
* properly handle choices, constraints on float/date/datetime fields
[vreg] object_by_id should not have been deprecated. Fix facets.
it was *designed* to be able to force an object retreival when selection
is potentially not possible.
For instance using select instead of object_by_id in get_facet totally
breaks the implementation since in get_facet we've not context result
set, and we ends up with a NoSelectableObject exception.