This PR introduces Traits as a new concept of the meta-meta-model Fame.
Whereas it can look too much for the meta-meta-model.
I believe it is important to use them.
Indeed, our relations are based on traits and they are not represented in the meta-meta-model.
This PR also should not break any tools already used in the image but only improve support of other tool (for instance, we can use FameJava to generate java meta-model from fame with trait support (java implementation uses interface), without traits, it is not possible).
This PR introduces Traits as a new concept of the meta-meta-model Fame.
Whereas it can look too much for the meta-meta-model. I believe it is important to use them.
Indeed, our relations are based on traits and they are not represented in the meta-meta-model.
This PR also should not break any tools already used in the image but only improve support of other tool (for instance, we can use FameJava to generate java meta-model from fame with trait support (java implementation uses interface), without traits, it is not possible).