message: Change error message for reducing number of ranks.
diff: @@ -744,8 +744,10 @@ void IOManager::readSidreHDF5(sidre::Group* datagroup,
  int num_files = getNumFilesFromRoot(root_file);
  int num_groups = getNumGroupsFromRoot(root_file);
  SLIC_ASSERT(num_files > 0);
  -// SLIC_ERROR_IF(num_groups > m_comm_size,
  -// "IOManager cannot read from files written by more ranks than are being used in the current run.");
  + SLIC_ERROR_IF(num_groups > m_comm_size && num_groups != num_files,
  + "IOManager attempted to read using a smaller number of processors "
  + << "than were used to produce the I/O files. This only can work if "
  + << "those files were created in file-per-processor mode.");
  if (m_baton)
  {
  