title: Grunt copy missing files
body: <p>For the last few days my <code>grunt copy</code> task is missing out some files. The task itself is the unedited task from SailsJS:</p>
  
  <pre><code>module.exports = function(grunt) {
  
      grunt.config.set('copy', {
          dev: {
              files: [{
                  expand: true,
                  cwd: './assets',
                  src: ['**/*.!(coffee|less|scss|sass|js)'],
                  dest: '.tmp/public'
              }]
          },
          build: {
              files: [{
                  expand: true,
                  cwd: '.tmp/public',
                  src: ['**/*'],
                  dest: 'www'
              }]
          }
      });
  
  grunt.loadNpmTasks('grunt-contrib-copy');
  };
  </code></pre>
  
  <p>I'm using Bower for dependencies within my <code>assets</code> folder which are copied to <code>.tmp/public</code> by Grunt.</p>
  
  <p>Some facts:</p>
  
  <ul>
  <li>it's always the same files which are missing (<code>lib/marked.js</code>, <code>angular-elastic/elastic.js</code>, <code>angular-ui-select/dist/select.js</code>, <code>angular-slugify/angular-slugify.js</code>)</li>
  <li>it worked for quite some time - I didn't change anything in the task, just in the <code>assets</code> (but not in the <code>vendor</code>) folder.</li>
  <li><code>grunt copy --verbose</code> also doesn't list these files.</li>
  <li>OS is win10.</li>
  </ul>