Move readmodel into cpp folder.
Properly format XML document for an element containing a single text leaf.

A element containing a single text leaf should be written in a single line without indentation. This special case is now detected and the proper formatting is performed.
Remove indentation from text formatting.

Text should never be indented in an XML file as text follows directly the tag end.
Add automatic GXmlNode output pointer typecasting.
Add XML example script.