Merge branch 'reduction' into 'master'

cmake_modules/local_subs.py

compute/pzgetrf.c

compute/zgetrf.c

control/compute_z.h

control/descriptor.h

control/descriptor_ipiv.c

include/chameleon.h

include/chameleon/runtime.h

include/chameleon/tasks.h

include/chameleon/tasks_z.h

runtime/CMakeLists.txt

runtime/openmp/codelets/codelet_ipiv.c

runtime/openmp/codelets/codelet_zipiv_allreduce.c

runtime/openmp/control/runtime_descriptor_ipiv.c

runtime/parsec/codelets/codelet_ipiv.c

runtime/parsec/codelets/codelet_zipiv_allreduce.c

runtime/parsec/control/runtime_descriptor_ipiv.c

runtime/quark/codelets/codelet_ipiv.c

runtime/quark/codelets/codelet_zipiv_allreduce.c

runtime/quark/control/runtime_descriptor_ipiv.c