Modify sky-pfi transformation to finalize with FF plane

The FF design position is compared with measured position by Kawanomoto-san (independently from Robert's estimation last year). The two positions has shift, rotation and scale difference as follows:

  dX = -1.855mm
  dY = -0.998mm
  dT = 0.765507deg
  dS = -7.67958e-04 (x0.999232042)

This should be taken into account when converting telescope coordinates to PFI coordinates.