XML:getText([path])
Return the value of the first text node that is attached to an element or null if there is no text node attached to the element.
The zero argument form returns the the value of the text node attached to the current element.
The one argument form returns the value of the text node attached to the element identified by the path string.
Example
doc = XML.parse([[<cfg><opt>foo</opt></cfg>]])
foo = doc:getText('/cfg/opt')
doc:goPath('/cfg')
foo = doc:getText()