Branch 2.0.x for Java 1.5 aligned with branch 2.1.x.

Improvements

• Added new factory method org.dom4j.io.SAXReader.createDefault(). It hase more secure defaults than new SAXReader(), which uses system XMLReaderFactory.createXMLReader() or SAXParserFactory.newInstance().newSAXParser(). SAXReader.createDefault() disable parsing of external entities in the SAX parser.