Checkpoint.  Fixed some bugs in table rendering.  Added more examples.
Render end productions in parsing table to_str.
Revamp table rendering to make column dividers split row dividers.
Code "cleanup" while trying to track down follow-set construction bug.
More cleanup.
Fixed bug in test input (follow-set computation was fine; the test was bogus).

Also, some better name choices for helper functions.
playing around with sourcegen ideas.