Reorder sections in nav.
Add to intro page.
Only highlight steps on hover when proof is editable.
Move code around in theorems.js and work on comments, prep for more edits.
Restructure generation of rewrite rules to support unnamed theorems ("facts").
Add memos field to Exprs, work on comments.
Comments.
In rules menu display axioms and theorems with their "formula"
if given, or their proved statement.
New function isIdentifier.
Modify rewriter generation to work with rather arbitrary "facts",
not just axioms.
Make rule menus for rewrites nicer, tidy up code a bit.