doc/articles/image_draw.html: Change ColorImage to Uniform
doc/articles/image_draw.html: Change ColorImage to Uniform

Fixes issue 3474.

R=nigeltao
CC=golang-dev
http://codereview.appspot.com/6048050

Committer: Nigel Tao <58ae08b3356928ff9c67562b4719487d54fe8348@golang.org>

apparentlymart/golang,tv42/old-go,dsriram/golang,pombredanne/go-deleteme,apparentlymart/golang,gnanderson/go,tv42/old-go,tv42/old-go,dsriram/golang,dsriram/golang,pombredanne/go-deleteme,pombredanne/go-deleteme,gnanderson/go,apparentlymart/golang,dsriram/golang,apparentlymart/golang,apparentlymart/golang,apparentlymart/golang,gnanderson/go,apparentlymart/golang,tv42/old-go,pombredanne/go-deleteme,dsriram/golang,pombredanne/go-deleteme,gnanderson/go,tv42/old-go,pombredanne/go-deleteme,tv42/old-go,tv42/old-go,dsriram/golang,gnanderson/go,dsriram/golang,pombredanne/go-deleteme,gnanderson/go,gnanderson/go