Improvements to formatting of _DX_DEBUG output
Improvements to formatting of _DX_DEBUG output

* Add colors and bolding selectively
* Insert sequence numbers
* Indent responses to make them visually distinct from requests

dnanexus/dx-toolkit,jhuttner/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit,jhuttner/dx-toolkit,dnanexus/dx-toolkit