A verbose label is a longer version of a label that can be used for

display purposes (such as in the Review menu) and for ARIA labels. By

separating these concepts, an action can have one representation in a

place like the Review menu and another in a place like the Quick Access

area without having to have two separate registered actions.
It's set up just like labels on the Python classes and JavaScript

model, and is opted into by action views.
The detailed menu template (used for the Review menu) prioritizes the

verbose label over the standard label. Standard menus and buttons use it

exclusively for ARIA labels.

Unit tests pass.
Tested that the Review menu had the correct labels and that buttons had

the correct ARIA labels.