fixing comment - need to include src dir
w01e01: toDigits implementation
w01e01: Replacing toDigits with a TCO implementation
w01e02: Implementing doubleEveryOther
w01e03: Implementing sumDigits
w01e04: Implementing validate
w01e05: Implementing Hanoi (3 pegs)
w01e06: Implementing Hanoi (4 pegs)
w01e06: Reimplementing Hanoi (4 pegs)

I realized that solving for fewer than three discs would just produce the
same result as "hanoi" for 3 discs, so just call out to that one.