More cleanup. Mostly readability and idiomatic ruby changes. Switch to
weirich method for all blocks. Switch to accessors as much as
possible. Remove extraneous parens. Clean up logic to spell out what
we're doing rather than rely on lame comments. Line stuff up. Etc.
Switch to StandardError. Oops.
More cleanup on robot_runner.rb, but also change @actions to a plain
hash instead of defaulting to 0. Why zero?!? Doesn't make sense for
strings or anything else really.