Change the title of the QUnit HTML file.
Add an exercise "convert to all caps."
Add a "remove all 'e' characters" exercise.

This one requires a regex for global substitution.
Add a hex-to-decimal conversion exercise.
Add a "decimal to binary conversion" problem.
Fix a typo in a hint.
Add a "power" math exercise.
Add a character position exercise.
Add an exercise for seconds since the Unix epoch.
Fix a Python hint: use bin() for binary literals, not int().
Add an exercise for hex colors.
Rename the Binary exercise to make room for a similar one.
Add a "binary to decimal" exercise.
Add a "replace digits with exclamation marks" exercise.
Add an exercise to count the number of digits in a string.
Tweak spacing of the exercise menu and display.
Expand a couple of hints.
Use Math.max() instead of finding the max by hand.
Don't move to the top of the page when clicking a link/anchor.
Allow a string to be broken up across lines, by inserting spaces.