Allow parse to accept either a file name or a file handle

[jandrew]

This is a feature of ParseExcel that I did not initially support

• [x] split out the XLSX File and IO::File types in the type library
• [x] add the changes to the Type library test suit
• [x] add a file_handle attribute to LibXML
• [x] Use a coercion in the workbook build to handle differences