fix webpack to handle node global functions

tests/all/main.rs

@@ -48,6 +48,14 @@ fn project() -> Project {
                 "webpack.config.js".to_string(),
                 r#"
                 const path = require('path');
+                const fs = require('fs');
+
+                let nodeModules = {};
+                fs.readdirSync('node_modules').filter(function(x) {
+                    return ['.bin'].indexOf(x) === -1;
+                }).forEach(function(mod) {
+                    nodeModules[mod] = 'commonjs ' + mod;
+                });
 
                 module.exports = {
                   entry: './run.js',
@@ -69,7 +77,8 @@ fn project() -> Project {
                     filename: 'bundle.js',
                     path: path.resolve(__dirname, '.')
                   },
-                  target: 'node'
+                  target: 'node',
+                  externals: nodeModules
                 };
             "#.to_string(),
             ),