Add definitions for the Node.js process API.
Treat Node.js events, stream, and child_process as general modules to properly type the "process" API.
Export the Node.js 'fs' module externs.
Update the return type of the Node.js Hash.update method.
Add more robust Node.js core annotations.
Attempt to properly handle JSON files.
Allow package.json to specify generic externs using the 'externs' key.
Merge pull request #1 from koop/koop-npm

Node.js: Update annotations, add "externs" keyword to package.json, and handle JSON files.