xml: replace Excel for XML file

[n0v1c3]

Determine if there is a manageable way to store all data in XML format while still being able to use Excel to maintain the data.

This will provide easier parsing of the data with other tools and reading from terminal while maintaining the easy front end provided by Excel.

[mikeboiko]

I think we should add a new switch/argument where the user can select if the settings are loaded from XML or the excel configuration spreadsheet. The default setting for this switch could be xml.

Something along these lines:
parser.add_argument('-sXL', action="settings_from_xl", default=false)

What do you think?

[n0v1c3]

If it is a settings only file I would suggest JSON so it could also be a string arg

tbl2xml -s <path to json file> and tbl2xml -s <json string>

This way scripts other scripts can build a json string and use this one or have a common file.