dh-make-node tool

I propose the addition of dh-make-node tool which, as the other dh-make-* tools, generates debian/ directory by reading package.json. The tool does the most of the tedious tasks:

• resolves the dependencies;
• generates test;
• creates a template of d/copyright;
• creates a watch file.

Of course the resulting debian/ directory requires a human review, but the amount of manual work is reduced.