First part of the big redesign of the histograms in Krita. This introduces a lot of new classes, but now every basic colorspace now has a working histogram (except wetsticky, which combines channels of uints with floats and even an enums). This design also opens the door to some more advanced histogram features in Krita which would otherwise be harder to do.

The histogram widget has now extra widgets to zoom in on histograms with more than 256 values for a channel, but don't expect anything polished because I plan refactoring the histogram widget and dialog in part two of the redesign.

svn path=/trunk/koffice/; revision=459321