Stereotypes
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Stereotypes is quite another story. In order to create a stereotype
one should create a Profile. Within this profile a Diagram can be created.
This diagram should accept only items that are useful within a profile:

- Classes, which will function as <<metaclass>>.
- Stereotype, which wil be the defined <<stereotypes>>.
- Extensions, connecting metaclasses and stereotypes.

and of course the usual: Comment, Association, Generalization and Dependency.

Thoughts:

- Profiles are reusable and its common to share them with different models.
- Stereotypes can only be owned by Profiles, not by (normal) Packages.
- We have to do a lookup if a MetaClass is actually part of the model.
- a stereotype can contain an image, that can be used in stead of its name
- Profiles should be saved with the model too. And iit should be possible to
  "update" a profile within a model.

Maybe it would be nice to create Stereotypes without creating the diagrams.
Via a dialog once can select which class (Operation, Class, etc.) is
stereotyped, which extra constraints apply and/or if you inherit from an
already existing stereotype. This way it's easy to save your stereotypes
apart from the model (and possibly in the model too) so they can be reused
in other models. 

I could create a special diagram window too that can be used to create
profiles. Profiles should be added to packages within the model.

This window should contain:
1. Name of the stereotype
2. Metaclass it applies to (Class, Operation, etc.)
3. If it is a subclass of an already existing metaclass
4. Constraints
5. Description
6. The profile it belongs to.

When a stereotype is used, an instance is created of the Stereotype
(meta)class. This is not really possible for our application. Gaphor should
figure out another way to do this. Should check XMI and see how they do it
(maybe a property is enough).

It looks like the stereotypes are more a concept than something that is
implementable in an application. The point is that the stereotypes you define
(instances of Stereotype) should be instantiated in your model when you create
a stereotyped class.

There is BTW no way to connect a stereotype with a class other than an
Association.

