Got rid of some compiler warnings because of const POD return values. I think it is unlikely that we will ever have return types that are modifiable as rvalue, so I think we can do without that const.
Merge branch 'master' of github.com:espressomd/espresso
Merge branch 'master' of github.com:espressomd/espresso
Merge branch 'master' of github.com:espressomd/espresso
Merge branch 'master' of github.com:espressomd/espresso
Merge branch 'master' of github.com:espressomd/espresso
Merge branch 'master' of https://github.com/HRZaheri/espresso
Merge branch 'master' of github.com:espressomd/espresso
Updated and added copyright headers.
Fixed compilation without MPI
Do not remove myconfig-sample.hpp when cleaning up.
Reformatted festures.def
Merge branch 'master' of github.com:espressomd/espresso
Fixed wrong file name in ug.
Distclean myconfig-sample.hpp
Merge branch 'master' of github.com:espressomd/espresso
Mmm1dgpu: move mpi.h dependents into a separate cpp file not compiled using nvcc.

This solves the issue that nvcc does not find mpi.h.
Integrated MMM1D_GPU into jenkins config files.
Some fixes to the compilation docs.
lattice.hpp inline function moved to lattice_inline.hpp