An xml element declaration in xml::dom
XML::DOM::ElementDecl extends XML::DOM::Node but is not part of the \s-1DOM\s0 Level 1 specification.
This node represents an Element declaration, e.g.
<!ELEMENT address (street+, city, state, zip, country?)>
\$1
Returns the Element tagName.
Returns and sets the model as a string, e.g. \*(L"(street+, city, state, zip, country?)\*(R" in the above example.