docs: add images and video to readme

README.md

@@ -18,6 +18,10 @@ Provides buttons for any D20 roll chat card to change the roll's advantage statu
 For example:
 If a d20 roll was rolled with advantage, the user will be able to set that to not have advantage or to instead be at disadvantage.
 
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+https://user-images.githubusercontent.com/7644614/158040905-cc9a94ee-6581-4c2c-badf-6de144d5997f.mp4
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 ## Out of Scope
 
 This module does not interact with any other module which might rely on the results of a dice roll (for example "Attack Roll Check D&D5e"). Any automations based on attack rolls, saving throws, etc would be far too complex to attempt to 'undo and redo' with the new result.