It's hard to find literature with the community tone we're going for, that
is consistent with the Zulip code of conduct, etc.
This commit removes the special tooling for Gutenberg plays, and changes the
text to be some mixture of scigen, Communications From Elsewhere,
chat.zulip.org, and various books from the public domain.
Create a generator script to pull lines from a play, enhancing
random lines with emoji, Markdown and other flair.
With numerous contributions from Rein Zustand and Tim Abbott to finish
the project.
Fixes: #1666.