add type="text/javscript" to script tag in tutorial.

browserid/static/developers.html

@@ -30,7 +30,7 @@
       <div class="number">1.</div>
       <p><b>Enable BrowserID:</b> Include the BrowserID JavaScript library in your site by adding a script tag to your <tt>&lt;head&gt;</tt></p>
 
-      <pre><code>&lt;script src="https://browserid.org/include.js"&gt;&lt;/script&gt;</code></pre>
+      <pre><code>&lt;script src="https://browserid.org/include.js" type="text/javascript"&gt;&lt;/script&gt;</code></pre>
     </div>
     <div class="step">
       <div class="number">2.</div>