Increase version to 0.3.2.0.

Ignore-this: 35afcc0f7a14fa08d87b9ec444625db9

darcs-hash:20141112231745-4d2ae-729bf73366c2e69966632618d4e68bda70fed450
Add better documentation to the Canvas module.

Ignore-this: ba7ba9842faa1c5e83b33ac2d9ad1ce7

darcs-hash:20141113221723-4d2ae-7c0b48e341a2965f700bf8310cf998138b0abac1
Update changelog.

Ignore-this: be6f8b81887811fdfa4e146a448a0dfe

darcs-hash:20141113222453-4d2ae-0c5791bda8f33c38d660c24184d2c23cd8d7d9cb