Git-garden - display your git branches in an orderly manner

Here's a result of running Git::Garden on git-garden: http://stepien.cc/~jan/git-garden.html . PNG backends require a bit of polish. An image generated by Gnuplot is http://i.imgur.com/A5KsC.png , and the one which went through Graphviz is http://i.imgur.com/6NL43.png (it's height is 6px).