`handlebars.js` not detected on windows

This [line here](https://github.com/dbashford/mimosa-handlebars-on-window/blob/37b6088622fd55cddca1abdd9312143f1e8855c4/src/config.js#L24) contains a *nix-like path separator:

```javascript
config.handlebarsOnWindow.isHandlebars = new RegExp( "\/" + config.handlebarsOnWindow.libName + "$" );
```

For Windows, you'd need to check for a backslash. At the moment, the module is unable to locate `handlebars.js` and so it never overwrites the file.

This could be fixed by modifying the regexp to take backslashes into consideration, but I was thinking that since you're just interested in the last portion of the path (base filename + extension), you could just use `path.basename()` and then compare that with `handlebarsOnWindow.libName`.

What do you think?