Trying to track down the reason for the integration of the standard LB_GPU not integrating.
Fixed bug preventing proper LB integration
minor fixes
new shan chen test added
compiles without unnecessary warnings
...
passes lb_gpu.tcl  but fails  lb_planar.tcl
test lb_planar_gpu.tcl not fully working, Heisenbug in the density field
couette flow test in  lb_planar_gpu.tcl passed. Hydrostatic pressure test still fails
passes test lb_planar_gpu.tcl
still working on initialization