Added ResourceAccess nodes for SchemaNode and SchemaRelationship
as well as for _schema/SchemaNode and _schema/SchemaRelationship
Check for CONTAINS rel type instead of DOMChildren only (which works in pages only)
Add ResourceAccess object for _schema/- URL as well
Send REMOVE_CHILD only for end nodes connected by a CONTAINS rel
Fixed typo in name
Store positions on unload,
reload canvas on schema changes,
improved display of initial rel type