Config: Moved scripts and styles into js/ and css/ dirs under public

Currently, brunch compiles everything in ``public/``
This PR will compile:
1. ``js`` files into ``public/js/``
2. ``templates`` files into ``public/js/``
3. ``css`` files into ``public/css/``

I know it might sound a personal preference. But I never saw any project that put everything right under public. :)