Implemented a cuda autodetection feature in the build system. It is completely backwards compatible but if no options concerning cuda are given during the configure stage, it tries to find cuda in /usr/local/cuda.
Some improvements on CUDA configureation.
Turned off cuda guessing by default, as LD_LIBRARY_PATH would need to be set for ESPResSo to run.
fixed the pressure tensor calculation for LB

and added a quite powerful testcase that
checks Couette and Poisseuille flow and
hydrostatic pressure in planar geometries
Merge branch 'kessel_master' into espresso-object-in-fluid
I used the citebox environment, clered mpi_rank calls, cleaned all the warnings at the compilation...