title: $ Is not defined scripts Gulp task
body: <p>Hi I am trying to run my scripts task in gulp. My scripts path is defined as follows:</p>
  
  <pre><code>scripts: {
          coffee: [
              'app/assets/scripts/**/*.coffee'
          ],
          js: [
              'src/js/*',
              'src/js/**/*'
          ],
          map: ['src/js/**/*.map']
      },
  </code></pre>
  
  <p>My original file paths are located in root/src/js/ and I want my scripts to be placed in their minified version inside root/app/assets/scripts/.</p>
  
  <p>My gulp task is as follows:</p>
  
  <pre><code>gulp.task('scripts', function() {
      return gulp.src('app/scripts/**/*.js')
          .pipe($.if('*.js', $.uglify({preserveComments: 'some'})))
          .pipe($.sourcemaps.init())
          .pipe($.concat('app.js'))
          .pipe($.sourcemaps.write('./'))
          .pipe(gulp.dest('app/assets/scripts'));
  });
  
  But for some reason I keep getting this error
  [13:28:46] ReferenceError: $ is not defined
      at Gulp.&lt;anonymous&gt; (C:\Users\Myuser\apps\myapp\gulpfile.js:165:9)
      at module.exports (C:\Users\Myuser\apps\myapp\node_modules\gulp\node_
  modules\orchestrator\lib\runTask.js:34:7)
      at Gulp.Orchestrator._runTask (C:\Users\Myuser\apps\myapp\node_module
  s\gulp\node_modules\orchestrator\index.js:273:3)
      at Gulp.Orchestrator._runStep (C:\Users\Myuser\apps\myapp\node_module
  s\gulp\node_modules\orchestrator\index.js:214:10)
      at Gulp.Orchestrator.start (C:\Users\Myuser\apps\myapp\node_modules\g
  ulp\node_modules\orchestrator\index.js:134:8)
      at C:\Users\Myuser\AppData\Roaming\npm\node_modules\gulp\bin\gulp.js:129:2
  0
      at process._tickCallback (node.js:355:11)
      at Function.Module.runMain (module.js:503:11)
      at startup (node.js:129:16)
      at node.js:814:3
  </code></pre>
  
  <p><strong>UPDATE</strong></p>
  
  <p>Hey I think you are both right. <code>$</code> was not defined and should be <code>$ = require('gulp-load-plugins')();</code>. However now that I am running <code>scripts</code>, I get the following error:</p>
  
  <pre><code>[15:24:46] TypeError: undefined is not a function
      at Gulp.&lt;anonymous&gt; (C:\Users\Myuser\apps\myapp\gulpfile.js:166:13)
      at module.exports (C:\Users\Myuser\apps\myapp\node_modules\gulp\node_
  modules\orchestrator\lib\runTask.js:34:7)
      at Gulp.Orchestrator._runTask (C:\Users\Myuser\apps\myapp\node_module
  s\gulp\node_modules\orchestrator\index.js:273:3)
      at Gulp.Orchestrator._runStep (C:\Users\Myuser\apps\myapp\node_module
  s\gulp\node_modules\orchestrator\index.js:214:10)
      at Gulp.Orchestrator.start (C:\Users\Myuser\apps\myapp\node_modules\g
  ulp\node_modules\orchestrator\index.js:134:8)
      at C:\Users\Myuser\AppData\Roaming\npm\node_modules\gulp\bin\gulp.js:129:2
  0
      at process._tickCallback (node.js:355:11)
      at Function.Module.runMain (module.js:503:11)
      at startup (node.js:129:16)
      at node.js:814:3
  </code></pre>
  
  <p>Again, another vague error "undefined is not a function", is this explicit? Is there a <code>$</code> function missing?</p>