Fix issue that deepTools give error when  handling single-file input
Fix issue that deepTools give error when  handling single-file input

chuan-wang/NGI-ChIPseq,chuan-wang/NGI-ChIPseq,ewels/NGI-ChIPseq,ewels/NGI-ChIPseq,ewels/NGI-ChIPseq,ewels/NGI-ChIPseq,chuan-wang/NGI-ChIPseq,ewels/NGI-ChIPseq,chuan-wang/NGI-ChIPseq