title: gulp-mocha how to pass the compilers flag?
body: <p>I'm trying to use the <a href="https://github.com/sindresorhus/gulp-mocha">gulp-mocha module</a> but can't figure out a good way to pass over the compilers flag.  Is there a way to include this in my gulp task?  Maybe in a separate pipe somehow?  </p>
  
  <p>Example if running mocha from command line (works fine)<br>
  <code>mocha --compilers .:my_compiler.js test/**/*.js</code></p>
  
  <p>Example if using gulp-mocha (but where can I specify a compiler)?  </p>
  
  <pre><code>gulp.task('test', function () {
      gulp.src(["test/**/*.js"], {
          read: false
      })
          .pipe(mocha({
              reporter: 'spec'
          }))
          .pipe(exit());
  });
  </code></pre>
  
  <p>I don't see a compilers option under the gulp-mocha plugin, so I'm thinking I need to somehow add the compilers by appending the text through a pipe somehow?  </p>