Add IntelliSense for Node.js modules!!!

This is only stage one; the next step is to add directory traversal when pressing `/` to get IntelliSense for including JS files within the current module (or in other modules).

Also shows descriptions from `package.json`, if present.

![node js module intellisense](https://f.cloud.github.com/assets/313894/1249453/9e2ae214-2ae0-11e3-87c7-947df1c15d26.png)



Also includes one more general fix.

This does not provide IntelliSense on the `require()`d object; I still don't see any possible way to do that. :frowning: