asXMLNode: Converts non-XML node objects to XMLTextNode objects
Description
This function is used to convert S objects that
are not already XMLNode objects
into objects of that class. Specifically,
it treats the object as a string and creates
an XMLTextNode object.
Also, there is a method for converting an XMLInternalNode
- the C-level libxml representation of a node - to
an explicit R-only object which contains the R values
of the data in the internal node.