Add generated code to GCM generator

[assaad]

It would be great to generate getter for indexes, relations, and references from the GCM model. get(IndexName)Index, get(RelationName)Relation, get(ReferenceName)Reference

Use case of this: when we want to check the size of the subnodes indexed or pointed by a relationship without actually resolving them.

[thomashartmann]

In case of bidirectional relations, this would allow you to use the generated API to create inconsistencies. I would rather propose to generate methods to get the size and/or keys of the relation without resolving the relation rather than return the Relation object itself. Something like:

public int getRelationNameSize() { return ((Relation) this.get(RELATIONNAME.name)).size(); }