updated draw example to use app data to show colors in buttons instead of the words

Ignore-this: 756b4d25bafe67b50d201860f9a5a710

darcs-hash:20140206232700-c21fe-5d748cd79579c743a60d18690a2f1642fe271063
added ability to draw images in the draw canvas

Ignore-this: 75017d69085f84931d4e8d0062aafa4b

darcs-hash:20140207040905-c21fe-499519c5914df644b406c3db57151c6f4b0902d3
swapped order of mouse move and draw operation

Ignore-this: 2357a11d1ab37afad744b82f13dd84c4

darcs-hash:20140207040936-c21fe-8153e5b811adbca7f9b01e9c14fab465ae661736