Fix some typos, broken links and other issues in extension docs

chrome/common/extensions/docs/templates/articles/tut_debugging.html

 <h1>Tutorial: Debugging</h1>
 
 
 <p>
 This tutorial introduces you to using
 Google Chrome's built-in Developer Tools
 to interactively debug an extension.
 </p>
 
 
@@ skipping 22 matching lines @@
       your browser's address bar.
     </p>
 
     <p>
       If the Hello World extension isn't already running,
       find the extension files and load them.
       If you don't have a handy copy of the files,
       extract them from this
       <a href="examples/tutorials/getstarted.zip" download="getstarted.zip">ZIP file</a>.
       See Getting Started if you need
-      <a href="getstarted.html#load-ext">instructions
+      <a href="getstarted.html#unpacked">instructions
       for loading the extension</a>.
     </p>
   </li>
 
   <li>
   Go to the Extensions page
   (<b>chrome://extensions</b>),
   and make sure the page is in Developer mode.
   </li>
 
@@ skipping 196 matching lines @@
     explore the
     <a href="http://www.chromium.org/devtools">Developer Tools site</a>,
     and watch some video tutorials.
   </li>
 </ul>
 
 
 
 <p>
 For more ideas,
-see the <a href="getstarted.html#summary">Now what?</a> section
+see the <a href="getstarted.html#next-steps">Now what?</a> section
 of Getting Started.
 </p>