title: What does "!" mean in file paths?
body: <p>I am reading over someone's <code>gulpfile.js</code> that I found, and came across an interesting character that I've not seen in file paths before; the <code>!</code> symbol. I tried to do some searches for this but yielded nothing.</p>
  
  <pre><code>gulp.task("min:js", function () {
      gulp.src([paths.js, "!" + paths.minJs], { base: "." })
          .pipe(concat(paths.concatJsDest))
          .pipe(uglify())
          .pipe(gulp.dest("."));
  });
  </code></pre>
  
  <p>Does the <code>!</code> have some particular meaning, here?</p>