Merge branch 'feature-mpi-comm-user' into 'master'

compute/pzgetrf.c

compute/zgetrf.c

control/control.c

control/descriptor_ipiv.c

coreblas/compute/CMakeLists.txt

doc/user/chapters/using.org

example/lapack_to_chameleon/step6.h

example/lapack_to_chameleon/step7.c

example/lapack_to_chameleon/step7.h

include/CMakeLists.txt

include/chameleon.h

include/chameleon/runtime.h

include/chameleon/runtime_struct.h

include/chameleon/struct.h

include/chameleon/struct_context.h

include/chameleon/tasks.h

runtime/CMakeLists.txt

runtime/openmp/codelets/codelet_ipiv.c

runtime/openmp/control/runtime_descriptor.c

runtime/openmp/control/runtime_descriptor_ipiv.c