update yo dependency

Attempting to install where other generators are already installed, and yo 1.1.2 is installed was giving the following error:

```
npm ERR! peerinvalid The package yo does not satisfy its siblings' peerDependencies requirements!
npm ERR! peerinvalid Peer generator-coffee-module@0.5.2 wants yo@>=1.0.0
npm ERR! peerinvalid Peer generator-gruntfile@0.0.9 wants yo@>=1.0.0
npm ERR! peerinvalid Peer generator-node@0.0.8 wants yo@>=1.0.3
npm ERR! peerinvalid Peer generator-node-coffee@0.0.3 wants yo@~1.0.3
```