Remove settings (rebased onto develop)



This is the same as gh-2313 but rebased onto develop.

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While reviewing gh-2300, noticed that the term "settings" was not removed when re-organizing the menu.

Test 1:
 * Select an item
 * Right-click and select the "Rendering Settings" item
 * Items in the "Rendering Settings" should no longer display the term Settings (only in the tooltips)

Test 2:
 * Browse a dataset
 * Right-click on an image
 * Check the Rendering Settings menu.