add pairend option for pairend data, the sample with multiple files but without pairend flag will be treated as replication.
add pairend option for pairend data, the sample with multiple files but without pairend flag will be treated as replication.
shengqh/ngsperl,shengqh/ngsperl,shengqh/ngsperl,shengqh/ngsperl