Paul Romano authored Sep 12, 2015 and Brad King committed Sep 11, 2015

The calls to find_program now use NAMES_PER_DIR so that the first executable
(e.g. h5pcc) appearing on their PATH will get chosen. The HDF5_PREFER_PARALLEL
variable swaps the search order when it is set to true in the event that a
directory being search contains both h5cc and h5pcc.