Require config when task shell starts

Config adds to the require paths so it needs to be required
before the handler starts so that web worker handlers have the
same require semantics as the main window.

src/stdlib/task-shell.coffee

@@ -20,8 +20,10 @@ self.callTaskMethod = (method, args...) ->
 # The worker's initial handler replaces itself when `start` is invoked
 self.handler =
   start: ({resourcePath, requirePath, handlerPath}) ->
+    self.resourcePath = resourcePath
     window.resourcePath = resourcePath
     importScripts(requirePath)
+    require 'config'
     self.handler = require(handlerPath)
     callTaskMethod 'started'