Visualize attacks

[jkrvivian]

Attacks can be performed with one-click button on the visualizer:

• [ ] Shimmer visualizer against our APIs, using the protonet.js glue.
  • [ ] @luca-moser should get in touch with designed people to make sure the final visualizer and explorer has the new design.
• [ ] Draft attack scenarios
  • [ ] evil spammer
• [ ] Add a new section for attack buttons
• [ ] record attacks
• [ ] replay attacks