Haobin's comments on the tutorial (in progress)

[FTRobbin]

I'm also working on a PR that fixes some minor issues not listed here.

1. It bothers me a lot that the six filenames are not in a single line in the HTML file.

Lesson 2

2. In the first exercise, I don't think the graph is large enough for the path rule to be significantly slower.

Nits

1. Might be helpful to link to the web demo and explain that you can use slide mode
2. Should use either egglog or egglog consistently across all lessons