raphael drawing implementation

Hey Pablo,
I've implemented Raphael instead of direct svg drawing. The functions are similar, but with a much better object structure. For example, now if you save the pattern object returned when you call the patterndraw.drawpattern() function, you can call functions like hideGrid() on it, so the full drawing don't need to be redraw, and just hides the grid.

There are still some pattern that don't render well (that men's shirt block...), so I keep working on it, and on some ui functions like zooming, panning...