Resolve minor terminology inconsistencies re. neurodiverse vs. neurodivergent

Why is this change being made?

Resolves some inconsistencies with the use of the terms "neurodiverse" vs. "neurodivergent".

As noted in the short-course description:

I'll refer to the group as neurodiversity. And as the individual, as a neurodivergent.

Similarly:

The word "Neurodiverse" refers to a group of people where some members of that group are neurodivergent.

To put in another way, the diversity in "neurodiverse" refers to the way people in a group vary neurologically from one another. That's similar to how diversity in general refers to diversity among people. A group can be made up of diverse people, but we wouldn't refer to an individual as "diverse".

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