Capture output from XML::Writer
This module implements a bare-bones class specifically for the purpose of
capturing data from the XML::Writer module. XML::Writer expects an IO::Handle
object and writes XML data to the specified object (or STDOUT) via it's print()
method. This module simulates such an object for the specific purpose of
providing the required print() method.
It is recommended that $writer->end() is called prior to calling $s->value() to
check for well-formedness.