PTFM-17058 Be paranoid about closure variable scope
PTFM-17058 Be paranoid about closure variable scope

In the absence of leads on PTFM-17058, eliminate the possibility of nested subroutine variables being modified from the outer scope.
jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,johnwallace123/dx-toolkit,johnwallace123/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,johnwallace123/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,johnwallace123/dx-toolkit,johnwallace123/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,johnwallace123/dx-toolkit,johnwallace123/dx-toolkit,dnanexus/dx-toolkit,johnwallace123/dx-toolkit,jhuttner/dx-toolkit