Fix: Use BTM from NPM. Allow local dynamic imports.
Add: Another problem written by Brian W.
     Footnotes that were accidentally deleted.
Fix: Correct BTM use per Brian W.
Clean: Remove unnecessary import (BTM is dynamically imported).
Fix: Update BTM to latest commit.
Fix: Correct namespace of dynamic imports.
Add: Local copy of bowtie math.
Add: dynamic imports supporting bow tie math.
Clean: Remove unused import.
Squash with prev
Fix: Better logic for static seeds.
Add: A better RNG.
Add: allow a JSON-provided static seed.
Fix: Use %[= and ]% tags, but avoid relying on EJS.
Revert: Go back to index.rst from 6a33115,
        which used %[= and %] instead of <script-eval> tags.
Fix: For debug, don't use hashed filenames.
Fix: Replace ejs with custom tags.
     Whitespace reformatting / cleanup.
Add: Problem written by Brian Walton.
Fix: Remove alert classes following 3df1418.
Add: Hooks, pass more info to dynamic problems.
Add: Dynamic questions.
Fix: Make CodeChat indents work.

… for testing.

…produces.

     Use a different problem type for dynamic problems.