Added usage section to documentation.
Added usage section to documentation.

Added usage information that describes how to use the DKAExpandingMenu
class in the documentation.

kkarayannis/DKAExpandingMenu,Adorkable-forkable/DKAExpandingMenu,Adorkable-forkable/DKAExpandingMenu,Adorkable-forkable/DKAExpandingMenu,kkarayannis/DKAExpandingMenu,kkarayannis/DKAExpandingMenu