Makefile: omp tests are now made with 8 threads; added more compilation and testing targets.
life_omptest.sh now uses "ompicc" version, and performs 3 different tests.
Makefile: "kepler" versions removed from target "all".
OpenMP: moved parallel regions to a single parallel region outside of the main loop, and added all necessary synchonization directives to the parts which need to be executed serially. Added "schedule(static)" clause to all "omp for" directives, as well as "collapse(2)" (commented out for now).