seq-data-to-lane-bam failed to skip all input bams when process multiple input bams

[lindaxiang]

Detailed Description

When there are multiple input bams, here needs to skip all the input bams. Otherwise the job will fail and report:
Error: unable to find read group info for rg_id in the supplied metadata (SONG Analysis)

Approach to address this

Let the samtools split generate the output into separate subfolder so as to avoid processing the input bams.

Testing

Need to add a new test to cover the case

[junjun-zhang]

addressed by #108 and #109