Changes in Mini-XML 2.1

• Added support for custom data nodes (STR #6)
• Now treat UTF-8 sequences which are longer than necessary as an error (STR #4)
• Fixed entity number support (STR #8)
• Fixed mxmlLoadString() bug with UTF-8 (STR #7)
• Fixed entity lookup bug (STR #5)
• Added mxmlLoadFd() and mxmlSaveFd() functions.
• Fixed multi-word UTF-16 handling.