More donate options

Hi!

I've been an eager user of Command-T since I first found it about a year ago. It's made me way more efficient as switching between files is done in a 1sec.

I'm opening this topic to propose to add an option to donate through Flattr. I'm using this system with other developers (and others), and as it makes it super-easy to donate, possibility of making recurring donations, etc.

It would be nice to see this option supported here so that I can contribute :)

Cheers