title: Copy only remaining files
body: <p>I would like to have a grunt task that copies only the files that have yet to be processed without having to exclude them specifically. For example: you can see in the gulpfile below I exclude <code>vue</code> files from the copy task as they have already been processed by the vue task. I would like to, instead of specifying a glop to exclude, exclude all files that a previous task has used as a src.</p>
  
  <pre><code>const gulp = require('gulp')
  const clean = require('gulp-clean')
  const vueify = require('gulp-vueify')
  
  gulp.task('vue', () =&gt;
    gulp.src('src/**/*.vue')
      .pipe(vueify())
      .pipe(gulp.dest('./dist')))
  
  gulp.task('copy', () =&gt;
    gulp.src(['src/**/*', '!src/**/*.vue'])
      .pipe(gulp.dest('./dist')))
  
  gulp.task('clean', () =&gt;
    gulp.src('dist')
      .pipe(clean()))
  
  gulp.task('default', [ 'vue', 'copy' ])
  </code></pre>