Allow `property` in Alias_Meta_and_Class_Attribute
Split `id` into `bare_id` and `index`

Prepare for support of rev-ref attributes for multiple entities.
Add `TFL.Meta.Property` class

* Support properties that work on class and instance

* Ease overriding of `getter`, `setter`, or `deleter` in subclasses

* Remove obsolete metaclass `M_Autoproperty`
Add property `ref_attr` to `_A_Rev_Ref_`
Add support for rev-ref attributes to MF3
Implement error handling for MF3 forms
Update translations