Fixed Java code to use ‘<‘ instead of ‘>’
Use createCopy(), otherwise an exception will be thrown.

The Dom4J element returned by element(“address”) still has its original
parent set. Adding this element to another node results in an
IllegalAddException. See Dom4Js Branch#add(Element element) JavaDocs.
The createCopy() method just copies the element without its parent and
therefore can be used to move elements betweens different trees.
Merge pull request #104 from sebhoss/upcaster-doc

Small fixes for the upcaster documentation