Feature: Infer local non-JS read dependencies (`fs.read`, `__dirname`, etc.)

[ryan-roemer]

We have dependency code like:

var STYLESHEET = fs.readFileSync(path.join(__dirname, '/public/style.css'), 'utf8')
var TEMPLATE = fs.readFileSync(path.join(__dirname, '/public/error.html'),

where we could infer some combination of

• fs.read*
• path.*
• __dirname

Indicates reading a non-JS-imported file.