Calculator: Actually remove the color declaration.

It turns out that https://github.com/duckduckgo/zeroclickinfo-goodies/issues/575 is still coming up because the comment is being uncommented. While I investigate the reason as to why that's happening, this should fix #575.

![8](https://cloud.githubusercontent.com/assets/81969/3935635/b5565822-2497-11e4-83a2-4dfd3d2eb7b0.PNG)