Performance improvement in PointToVector conversion.
Added (boost's) hash_value function for statismo::VectorType.
Separated Kernel interface and basic kernels from kernel combinators.
New class SpatiallyVaryingKernel with an example of how to use it.
Cleanup and minor improvements.
Merge branch 'temp' into spatially_varying_kernel
Merge branch 'factoredout_nystrom' into spatially_varying_kernel

Conflicts:
	modules/VTK/src/vtkStandardMeshRepresenter.cxx
	modules/core/include/Kernels.h
address some comments
Made tempering function dependent on the reference mesh's center of mass.

So far the tempering function in the example was defined such that it would assign the value
0 for points with x-component larger than zero and 1 otherwise. This would only be applicable for
meshes that are centered on the origin. We made it more general, by using the center of mass for the
definition of the tempering (i.e. we temper values that are larger than
the center of mass).
own implementation of centerOfMass for vtkPolydata
minor performance improvement
replaced all instances of std::auto_ptr with boost::scoped_ptr
Merge pull request #99 from statismo/auto_ptr_to_scoped_ptr

auto_ptr to scoped_ptr
Merge pull request #94 from statismo/spatially_varying_kernel

Spatially varying kernel