Continues the porting process up to and including nexts().
- Sections that require a code review:
- - rset(), lines 2521 -> 2523 (Variable may be in degrees or radians, function may require degrees or radians)
- - dobend(), lines 3073 -> 3077 (A strangely placed GOTO is changed to an if)
- - nexts(), lines 3189 -> 3291 (Was a mess of GOTOs, changed to functions)