Add Menu.removeMenuDivider()
Add Menu.removeMenuDivider unit tests
Remove all menu items before removing menu
Fix problem with removing dividers.  Add remove menu (native) unit tests.
Replace not.toBeNull() with toBeTruthy()
Remove extra spaces
Merge pull request #5384 from lkcampbell/fix-remove-menu

Menus.removeMenu cleanup: remove all menu items and dividers prior to removing menu