Abyssal

Minor API changes and bug fixes

API Changes

• node and edge data is namespaced under 'sbgn' instead of the global namespace (this will allow less conflicts with other cytoscape.js extensions who populate the global namespace with common names such as id, class, etc.
• state variables and units of information are kept in their own separate arrays instead of one
• auxiliary items had a 'clazz' field which has been changed to 'class'