Constructs a rotor.
If turnovers are not specified, the rotor has no turnover notches,
otherwise, for example, if turnovers are 1 and 25, the next rotor
steps when this rotor steps from B to C and from Z to A.
If ringOffset is 2, it corresponds to "C-03".
Constructs a rotor. If turnovers are not specified, the rotor has no turnover notches, otherwise, for example, if turnovers are 1 and 25, the next rotor steps when this rotor steps from B to C and from Z to A. If ringOffset is 2, it corresponds to "C-03".