Finished modifying all of:
LinearAlgebraDistributionHelpers::concatenate(..)
DoubleVectorHelpers::concatenate(...)
DoubleVectorHelpers::split(...)
DoubleVectorHelpers::concatenate_without_communication(...)
DoubleVectorHelpers::split_without_communication(...)
CRDoubleMatrixHelpers::concatenate_without_communication(...)
CRDoubleMatrixHelpers::concatenate(...)