does not build with starpu/simgrid if symbols starpu_mpi_cache_flush and starpu_mpi_cache_flush_all_data

refix the problem of starpu mpi function detection - with the complete path of mpi libraries the test fails... with -L/... and -l it succeeds

trailing whitespaces

Fix a large bunch of warnings, and there are still mistakes that should be fixed before the SC release

At the user levl, we wait for a sequence. We need to add a MORSE_Barrier function that waits for all sequences currently running

some cublas kernels can be used without magma only with CHAMELEON_USE_CUDA define - fix this mistake in cudablas files

Fix build with starpu1.1 which doesn't have starpu_mpi_comm_{rank,size}: let's just call RUNTIME_comm_{rank,size} which already do things properly