Shift various things from south_africa to spinner.

All the things below appear to be general enough that they could be
defaults for the carousel from the spinner app rather than coming
from south_africa.

As the country_app appears before spinner in installed_apps, they
can be overridden by providing them in the country_app itself.
Whitespace changes
Replace featured person with carousel (NG)

For issue 1250, replace the featured person on the right hand side
of the home parge with a carousel like ZA.

Styling is obviously very basic.
Reorganise sass to share some carousel stuff.

Looks OKish for nigeria but I've not yet checked south_africa as
I don't have a dev site with a good enough database.