New modes and improvements

[mirko-laruina]

New modes (total uploaded and total transferred), font-size and width fixes and some slight performance improvement

I forked the project and made some changes long time ago with the idea of developing it further, but since I haven't done it I think it is better to make a PR. As said, I've added two more modes and made slight improvements. Before merging, if you want to, you should revert (some of) the edits made in readme and metadata.json.