Issue 206 - Add a pref for suppressing the first run page

lib/ui.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 817 matching lines @@
         if (subscription instanceof DownloadableSubscription && !subscription.lastDownload)
           Synchronizer.execute(subscription);
       }
     }
 
     if (!addSubscription && !addAcceptable)
       return;
 
     function notifyUser()
     {
+      if (Prefs.suppress_first_run_page)
+        return;
+
       let {addTab} = require("appSupport");
       if (addTab)
       {
         addTab(window, "chrome://adblockplus/content/ui/firstRun.html");
       }
       else
       {
         let dialogSource = '\
           <?xml-stylesheet href="chrome://global/skin/" type="text/css"?>\
           <dialog xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" onload="document.title=content.document.title" buttons="accept" width="500" height="600">\
@@ skipping 1106 matching lines @@
   ["abp-command-contribute", "command", UI.openContributePage.bind(UI)],
   ["abp-command-contribute-hide", "command", UI.hideContributeButton.bind(UI)]
 ];
 
 onShutdown.add(function()
 {
   for (let window in UI.applicationWindows)
     if (UI.isBottombarOpen(window))
       UI.toggleBottombar(window);
 });