If symmetries are used to reduce the number of k-points,
this variable defines whether time-reversal symmetry is taken
into account or not. If it is set to no, the k-point
sampling will not be reduced according to time-reversal
symmetry.
The default is yes, unless symmetries are broken in one
direction by the SymmetryBreakDir block.
Warning: For time propagation runs with an external field,
time-reversal symmetry should not be used.