[ptx] small hugin bugs/questions

[Dan Scholnik]

Using hugin recently I found that the preview window doesn't apply
vertical and horizontal shifts ("d" and "e" parameters), or doesn't do
so correctly.  My camera optimizes pretty consistently to about -10
horizontal and -30 vertical, although I gather most folks shooting
digital with a rectilinear lens don't bother to use d and e.

(I really did try to figure out how to fix it myself, but I got lost
following the classes around...)

Also - what does the tooltip on d and e mean about linked d and e not
working in the optimizer?  It seems to work fine here.

Dan