Extension docs: Cleanup after there's only one version.

chrome/common/extensions/docs/templates/json/intro_tables.json

 {
   // TODO(epeterson) Generate permissions information dynamically.
   "alarms": {
     "Learn More": [
       {
         "link": "event_pages.html",
         "text": "Event Pages"
       }
     ],
     "Permissions": [
@@ skipping 377 matching lines @@
     "Permissions": [
       {
         "class": "code",
         "text": "\"storage\""
       }
     ]
   },
   "syncFileSystem": {
     "Learn More": [
       {
-        "link": "http://developer.chrome.com/trunk/apps/app_storage.html",
+        "link": "app_storage.html",
         "text": "Manage Data"
       },
       {
         "link": "https://developers.google.com/live/shows/83992232-2001/",
         "text": "Chrome Office Hours: Synched File System"
       }
     ],
     "Permissions": [
       {
         "class": "code",
@@ skipping 91 matching lines @@
   },
   "windows": {
     "Permissions": [
       {
         "class": "code",
         "text": "\"tabs\""
       }
     ]
   }
 }