Multi Species Particle Load from hdf5

- rewrite how partilces are loaded from HDF5 file
- add support for arbitrary species count
- particles load now done on gpu
- remove old method
- SimulationHelper: show init time in output

~~**Please do not merge before #514**~~
> cuda-memcheck --tool racecheck shows sometimes warnings if we not do this ...

that should be still the case, nevertheless discussion in #518