Reads a binary PList file and returns it as a NanoXML XMLElement.
The NanoXML XMLElement returned by this reader is equivalent to the
XMLElement returned, if a PList file in XML format is parsed with
NanoXML.
Description about property list taken from
Apple's online documentation:
"A property list is a data representation used by Mac OS X Cocoa and Core
Foundation as a convenient way to store, organize, and access standard object
types.