title: How to specify browserify extensions in package.json?
body: <p>In package.json:</p>
  
  <pre><code>...
  "browserify": {
    "transform": [
      "coffee-reactify"
    ],
    "extension": [ ".cjsx", ".coffee", ".js", ".json" ],
    "extensions": [ ".cjsx", ".coffee", ".js", ".json" ]
  },
  ...
  </code></pre>
  
  <p>When using browserify <code>transform</code> option works as expected, however browserify is not seeing <code>extension(s)</code> options - it throws error and I have to pass extension options manually to browserify...</p>
  
  <hr>
  
  <p>in gulpfile.coffee</p>
  
  <pre><code>b = browserify
    entries: './' # ./ = root = directory where package.json is
    debug: true
  b.bundle()
  .pipe(source('client.js'))
  .pipe(buffer())
  .pipe(gulp.dest(distDir))
  </code></pre>
  
  <p>in package.json</p>
  
  <pre><code>"browser": "src/client/client",
  "browserify": {
    "transform": [
      "coffee-reactify"
    ],
    "extension": [
      "cjsx",
      "coffee",
      "js",
      "json"
    ]
  },
  </code></pre>
  
  <p>src/client/client.cjsx</p>
  
  <pre><code>otherModule = require './other-module' # other-module.cjsx
  </code></pre>
  
  <ol>
  <li><p>When I remove <code>coffee-reactify</code> from <code>transforms</code> in package.json then browserify throws error <code>Parsing file .../src/client/client.cjsx: Unexpected token (2:16)</code></p></li>
  <li><p>When I put back <code>coffee-reactify</code> to <code>transforms</code> in package.json, then browserify successfully parses <code>client.cjsx</code> as long as I wont require any other <code>.cjsx</code> files from inside of <code>client.cjsx</code>. So for the example code of <code>client.cjsx</code> above browserify throws error: <code>Cannot find module './other-module' from '/src/client</code> - browserify still does not recognize extension...</p></li>
  </ol>
  
  <p>So browserify reads package.json (recognizes package.browserify.transforms and package.browser fields but it does not recognize extensions)</p>