Add possibility to control the footnote number

[troosan]

This will allow you to use another numbering for the footnote reference.

• 1, 2, 3 (default)
• I, II, III
• i, ii, iii
• A, B, C
• ...

You can also decide to put all footnotes at

• the end of the document
• the end of the section
• the end of the page (default)

You can also decide when to restart from 1

• continuous (default)
• each Section
• each Page

And finally you can decide not to start with 1

[troosan]

I should probably add the possibility to set the properties for the whole document, so you don't have to repeat it for each section ...