1. add placeholder for shape toolbar
2. add (not working!) line for addthis sharing toolbar.
hmm got double wide (ie 2 bars: color and brush) working on iPad. Still not satisfied: should whole thing be centered as a whole? Currently canvas is centered. slightly problematic when window w < h
add GUI images.
1. get brush selectors sized and images in. TODO highlight and actually change the brush to those shapes.
2. shorten a name
avoid drawing mouse when in pure touch mode. (mouse doesnt show until we get a mouse event)