A graphical notation for metamodelling

[louismrose]

Eugenia Live currently supports JSON and Eugenia notations. It might be easier for domain experts to customise the palette using a graphical notation.

[JoostvanPinxten]

Some of the ideas, based on the discussions we've had during this summer, we would like to be able to:

• use the properties to show a preview manifestation of a shape
• provide 'placement definitions' for contained items (like InputPort or OutputPort elements of an Processor element), this could be similar to the Dynamic Ports + Template definitions used in MetaEdit+.
• use meta-information of a BasicShape to let a user properly define its (possibly dynamic) properties (e.g. size, colors, borders, positions, etc) and bindings to Element properties

This is not an exhaustive list, and most of the above can be considered stretch goals (i.e. nice to have).