include/rank_filter.hxx: Add operator to write out arrays.
include/rank_filter.hxx: Add operator to write out arrays.

nanshe-org/rank_filter,nanshe-org/rank_filter,DudLab/rank_filter,jakirkham/rank_filter,jakirkham/rank_filter,nanshe-org/rank_filter,DudLab/rank_filter,jakirkham/rank_filter,DudLab/rank_filter