exp/draw: add Point.Eq, Point.Mul, Point.Div, Rectangle.Size methods
exp/draw: add Point.Eq, Point.Mul, Point.Div, Rectangle.Size methods

R=nigeltao, nigeltao_golang, rsc
CC=golang-dev, r
http://codereview.appspot.com/2192048

Committer: Nigel Tao <58ae08b3356928ff9c67562b4719487d54fe8348@golang.org>
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go