UML22 — Move Comment into Basic and add Kind

Move Comment into Basic and add Kind
The ability to annotate and describe elements and diagrams is pretty
fundamental so should be included in Basic.
There should also be the recognition that there are different kinds of
comment: for example most tools have a dialog allowing people to enter a
Description for an Element; and separately may allow the element to be
annotated on diagrams in a particular context. At the moment there is no
way to distinguish these.
The UML Metamodel itself is an example of the need for different kinds
of Comment: each Class has a number of distinct sections (e.g.
Description, Semantics, Notation).
Hence there should be a 'kind' attribute on Comment to reflect this.

Disposition: Closed, no change