Node type documentation

Started expanding the node type chapter.
I thought it would be cool to list the examples in all the available formats, as with the Symfony documentation. But I have some questions:

- Is it practical to list PHP examples? Is it possible to define a node type (with property and child node definitions) in a single PHP file - or would we have to list a class for each definition? This would be far too verbose.
- Are there any other formats that can be readily used with PHPCR other than CND? Such as XML?


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