Include newer karma-requirejs

On my machine, running `npm install` resulted in this dependency not being satisfied:
```npm ERR! peerinvalid The package karma-requirejs does not satisfy its siblings' peerDependencies requirements!
npm ERR! peerinvalid Peer karma@0.10.10 wants karma-requirejs@~0.2.0```

Bumping the `karma-requirejs` version was sufficient to fix things.
Merge pull request #235 from scw/patch-1

Include newer karma-requirejs