Recognize NPM Node packages

[balusarakesh]

When using scancode to scan a codebase it must detect npm packages based on package.json and node_modules directory trees.
The basic code is already in, but need to be plugged in actual scans

[balusarakesh]

already avaliable

[pombredanne]

This is not plugged in the scan proper yet

[pombredanne]

All merged and fixed