This is more of a Pull Request For Comment than a Pull Request. I don't think it's ready to be merged yet. ;)
I've created an alpha version of a Kivy "Gesture Box" that interprets gestures on the screen and issues an on_gesture event if they occur. If a gesture isn't recognized, the touch event is passed through to any child widgets of the box.
Things that need commenting on:
Those big long strings could do with a bit more explanation. I'm not entirely sure I understand them and what they do.
You may be interested in: #638 but neither me nor bionoid had had time to finish the work. It's basically a gesture recognizer, you can look at the demo to see how it works. First you train it giving it 1 or more examples, then it recognizes it.
Erm, I have simply lost this code because I didn't put it on a separate branch.
Meh, it wasn't functional anyway. ;-)