Bug#942523: fallback to npm registry tarballs when upstream git repo is missing

[Pirate Praveen]

Package: pkg-js-tools
version: 0.9.17

$ add-node-component -if babel-plugin-mamacro
Thread 1 terminated abnormally: No repo found for 0.0.7 version at 
/usr/share/perl5/Debian/PkgJs/Npm.pm line 65.
Component babel-plugin-mamacro not found in npm registry at 
/usr/bin/add-node-component line 173.