moved vtk-independent functionality from VtkRaster to Raster and modified existing functionality in Raster so that everything fits.

E.g. nullptr is introduced in 4.6.

Boost integration

refactored image reading routines such that alpha-channels are ommitted from double arrays and only inserted right before conversion to vtkImageData object (where this information is needed)

Note that the flags are only appended, not substituted.

Fix errors with intel compiler

On CMake 2.8.5 the Boost integration was not working on Windows.

Improve points.

This clarifies comparison operations (and also corrects them) on points. Tests included.

Fixed include and linker errors on Linux (GCC) because FindPackage(Boost) sets Boost_INCLUDE_DIRS to a wrong path when Boost was not found.

Cmake compiler flags

removed unused comparsion operations lessX(), lessY(), lessZ()

Improve TemplateVec class