[CREATE] Lens correction database

[Udi Fuchs]

> So I think that your blackbox covers 99% of applications out there, but
> unfortunately to please the remaining 1%, you will need to expose some more
> functions in the public API.

I think that UFRaw also goes into this 1%. First, for the interactive
interface it would also require handling of tiles, otherwise it will
be too slow. Second, handling corrections of raw files could make use
of the raw data, and therefore require different algorithms.

Udi