add interface Identifier to AdaptationGroups to enable auto generated UID

tools.descartes.dni.adaptation/model/DNIMM3AP.xcore

...tation/src/tools/descartes/dni/dnimm3ap/DNIAPPackage.java

...on/src/tools/descartes/dni/dnimm3ap/IAdaptationGroup.java

...c/tools/descartes/dni/dnimm3ap/impl/DNIAPPackageImpl.java

.../descartes/dni/dnimm3ap/impl/LinkAdaptationGroupImpl.java

.../descartes/dni/dnimm3ap/impl/NodeAdaptationGroupImpl.java

...ni/dnimm3ap/provider/LinkAdaptationGroupItemProvider.java

...ni/dnimm3ap/provider/NodeAdaptationGroupItemProvider.java

...ools/descartes/dni/dnimm3ap/util/DNIAPAdapterFactory.java

...on/src/tools/descartes/dni/dnimm3ap/util/DNIAPSwitch.java