Current limitations

Not working, but currently being fixed:

• Proper sampling of reaction and diffusion in 1D and 2D: The framework routines are there, but still use the wrong Green's Functions to sample from it.
• Interactions between the 1D-, 2D- and 3D-worlds: Particles up to now can only be defined within their "own" world, i.e. once they are defined on a nD-submanifold they will only move and interact with particles on this submanifold. Interactions between e.g. membrane bound particles and bulk particles do not work yet.