Skeleton rendering when waiting for data to load

[danalexilewis]

By default atomic-dog should be rendering skeletons of content while waiting for data to load into the browser. this is the "accepted ux norm" of apps now.

I have added an issue to the react-atomic-template repo suggesting this may be part of it using skeletor - if it is concluded that it is not part of this we will have to work out where it does belong in atomic-dog