this is a small tool to create a new stub bam file with all real readgroups and data removed
so users can share the full bam index but a (small) bam file containing only a spartan header.
The index is left unchanged and just copied to a new file with an unformative name.
usage is like:
anonymize-for-indexcov test1 *.bam
this will create sample_test1_0001.bam, sample_test1_0001.bam.bai ... sample_test1_$n.bam, sample_test1_$n.bam.bai
which can be shared.