iFit/uminus

 Implement -w1 for objects

   >> w = -w1

%   Overloaded methods:
      sqw/uminus
      testsigvar/uminus
      sigvar/uminus
      IX_dataset_3d/uminus
      IX_dataset_2d/uminus
      IX_dataset_1d/uminus
      sqw/uminus
      sigvar/uminus
      d4d/uminus
      d3d/uminus
      d2d/uminus
      d1d/uminus
      d0d/uminus
      codistributed/uminus
      gpuArray/uminus
%   Reference page in Help browser
      doc uminus