Add A New Slide

## We Need More Slides
Grab another octocat and create a new slide from scratch.
If you need help, check out the Appendix in the training manual.

Start by inspecting the repository structure to find how existing slides are stored, then read the Appendix in the training manual for the expected format. Create a new slide from scratch with another octocat; done means the repository contains the additional slide in the same structure as the existing slides.

索引モデルが issue の本文から書いたものです。