Example code in documentation for many-to-many Merge Class

[johnmckinzie]

The documentation speaks to a Merge Class for many-to-many relationships.

Note: Ruby requires a class to be defined before using it as a parameter, therefore, you should declare all classes that are contained within others, before the one in which you use them. If you want to have circular relationships, you need to define a Merge Class pointing to the same table and content type as the desired class (defined below).

It would be helpful to add example code that shows how you might go about this.