TestLoop: use OpenMP and OpenMP macros

TestLoop: use OpenMP and OpenMP macros

TestLoop: add test directory

TestLoop: shuffle order of Fortran clauses some more

this is to try and catch failures in the macros for "odd" placements

TestLoop: fix assumed atomicity of += operation

TestLoop: fix race condition introduced into Fortran tests

TestLoop: adapt to presence of cctk_tile_min and cctk_tile_max

TestLoop: adapt to OMP_PRIVATE macros acception ijk variables

TestLoop: adapt to OMP_PRIVATE macros accepting normal direction