Added support for options when defining transforms

`bundle.transform` has [two arguments](https://github.com/substack/node-browserify#btransformopts-tr).

With this, you can specify options with a transform while still being able to specify the transform name/function like normal:
```js
karma.set({
    frameworks: ["browserify"],
    // ...
    browserify: {
        transform: [
            'coffeeify',
            ['envify'],
            [{global: true}, 'debowerify']
        ]
        // ...
    },
    // ...
});
```