Description of topic explorer should only appear when topic bars load successfully

[JaimieMurdock]

For example, neo-kantianism does not have working bars yet, so the text should be hidden.

A class or id with a style that defaults to hidden should be added to the <p> tag containing the text.

When the bars load (from javascript in inphosite/templates/entity/singlebar.html] then we should set that <p> to visible.

That would be added here: https://github.com/inpho/inphosite/blob/master/inphosite/templates/entity/singlebar.html#L96

[colinallen]

Neo-Kantianism is not in the current hypershelf model as it was published in May 2018 and models are spring 2019. We are now 18 months behind so need a method to deal with that.