=== ATTENTION: CAMPVis does compile, but image representation conversion not yet functional again! ===

Revising ImageData concept step 2:
 * Removed all ImageDataXYZ classes
 * Introducing GenericAbstractImageRepresentation<T> and its GenericAbstractImageRepresentation<T>::ScopedRepresentation
 * Updated all processors and pipelines to use ImageRepresentationXYZ instead of ImageDataXYZ and the implicit conversion feature

git-svn-id: https://camplinux.in.tum.de/svn/campvis/trunk@401 bb408c1c-ae56-11e1-83d9-df6b3e0c105e