Merge 2 CSS files

[beven]

At the moment there is an App.css and main.css. We only need one for the time being.
Let's merge them into a main.css and put it in a "style" folder.

[rowhitswami]

@beven I'd like to take this one.

[rowhitswami]

#21 Please note.

[paolomangiadev]

@rowhitswami no need to reference the main.css in index.html as it's already imported in main.js, also there are some issues with classes as they were named "class" instead of "className" :) check #22

[rowhitswami]

#21 I removed css reference from index.html