[ptx] SpaceTransform class

[alexandre jenny]

Let's go :

I've finished the SpaceTransform class which replace the PanoToolsInterface
class.
It's quite compatible (except some namespace issues) and provide all the
transformation which were available in panotools directly in hugin without
any link anymore to pano12.dll.

I used the tests/transform.cpp to check I got the same result with this
class and it worked great.
So if we want we can already remove the dependency of hugin to pano12.dll

Some remarks about the calculation in pano12 :
- It's possible to have an output format (I really said output) as fisheyes
lens ...
We didn't provide such format in hugin (just rect, pano, erect). Should we ?

- In the preview windows, I have a good output of the image (well remapped)
but not the outline border, do you have the same ? (I didn't check that
before my modifications)

- The SpaceTransform class is actually just a manual wrapper to panotools
without panotools. But in the future, when the parameters are really fixed
(interface also), it will be rewritten for speed.

Alexandre