Eclipse Papyrus 6.0.0

Papyrus 6.0:

-we will reduce the dead code in the generated diagram code for GMF by introducing abstract classes.

-we have worked on tools to validate all customization models

- we have added a library to be able to connect a Xtext editor as a diagram editor or a table editor.

- we have added a set of fixes

Note that all the relatives: Sysml 1.6, Moka, designer... have also been reworked to be compatible with papyrus 6.0.