Guy: add state variables for walking
Guy: rename `can_walk` -> `can_walk_really`
Implement rolling for guy
Guy: cause roll_really start to stop walk_really
Guy step: move spd assignment
Fix dependency directives in structure.js
Fix syntax
Prevent Guy from rolling while rolling
Recolor guy to purple when rolling_really
Enable roll_really initially
Fix up roll physics
Disallow roll_really on roll_really_stop