added the sitewide 404 phonegap/phonegap.github.io#143

Author: GarthDB

404.html

@@ -0,0 +1,12 @@
+---
+permalink: /404.html
+title: Page not found
+layout: default
+body-class: no-subheader
+---
+<div class="four-oh-four">
+  <h1 class="four-oh-four-title">404</h1>
+  <p class="four-oh-four-description">Sorry, the page you are looking for does not exist.</p>
+  <div class="four-oh-four-image"><img src="http://phonegap.com/images/landspeeder_white_border.png" alt="Landspeeder"/></div>
+  <a href="/getstarted/" class="button--cta">Speed to the homepage</a>
+</div>