remove unused webpack require

Author: davidsbailey

apps/Gruntfile.js

@@ -2,7 +2,6 @@ var chalk = require('chalk');
 var child_process = require('child_process');
 var path = require('path');
 var fs = require('fs');
-var webpack = require('webpack');
 var _ = require('lodash');
 var logBuildTimes = require('./script/log-build-times');
 var webpackConfig = require('./webpack');