• Removed automatic prefixing of attribute names when using a namespace.
  
• Added 'qualifiedAttributes' constructor option to emulate prior attribute
  prefixing behavior.
  
• Always syntax check attribute names under strict conformance.
  
• Add documentation on using Tie::IxHash to get predictable attribute ordering.
  
• Allow tag 'AUTOLOAD'.
  
• Fixed bug with default namespace.
  
• More tests