Updated README for webpack instructions (#412)

README.md

@@ -58,7 +58,7 @@ node.js library usage of bunyan in your apps.
 - custom rendering of logged objects with ["serializers"](#serializers)
 - [Runtime log snooping via DTrace support](#runtime-log-snooping-via-dtrace)
 - Support for a few [runtime environments](#runtime-environments): Node.js,
-  [Browserify](http://browserify.org/), [NW.js](http://nwjs.io/).
+  [Browserify](http://browserify.org/), [Webpack](https://webpack.github.io/), [NW.js](http://nwjs.io/).
 
 
 # Introduction
@@ -1149,6 +1149,7 @@ Node-bunyan supports running in a few runtime environments:
 - [Node.js](https://nodejs.org/)
 - [Browserify](http://browserify.org/): See the
   [Browserify section](#browserify) below.
+- [Webpack](https://webpack.github.io/): See the [Webpack section](#webpack) below.
 - [NW.js](http://nwjs.io/)
 
 Support for other runtime environments is welcome. If you have suggestions,
@@ -1256,6 +1257,29 @@ var log = bunyan.createLogger({
 log.info('hi on info');
 ```
 
+## Webpack
+Webpack can work with the same example Browserify above. To do this, we need to make webpack ignore optional files:
+Create "empty-shim.js":
+```javascript
+// This is an empty shim for things that should be not be included in webpack
+```
+Now tell webpack to use this file for
+[optional dependencies](https://webpack.github.io/docs/configuration.html#resolve-alias)
+in your "webpack.config.js":
+```
+resolve: {
+    // These shims are needed for bunyan
+    alias: {
+        'dtrace-provider': '/path/to/shim/empty_shim.js',
+        fs: '/path/to/shim/empty_shim.js',
+        'safe-json-stringify': '/path/to/shim/empty_shim.js',
+        mv: '/path/to/shim/empty_shim.js',
+        'source-map-support': '/path/to/shim/empty_shim.js'
+    }
+}
+```
+Now webpack builds, ignoring these optional dependencies via shimming in an empty JS file!
+
 # Versioning
 
 All versions are `<major>.<minor>.<patch>` which will be incremented for