Move storing "last updated at" time to the app config

This way the config.php file is not changed every time you go to the
personal page. Step to make it possible to have a read-only config.php
most of the time

lib/setup.php

@@ -77,8 +77,6 @@ class OC_Setup {
 			OC_Config::setValue('datadirectory', $datadir);
  			OC_Config::setValue('dbtype', $dbtype);
  			OC_Config::setValue('version',implode('.',OC_Util::getVersion()));
- 			OC_Config::setValue('installedat',microtime(true));
- 			OC_Config::setValue('lastupdatedat',microtime(true));
 			if($dbtype == 'mysql') {
 				$dbuser = $options['dbuser'];
 				$dbpass = $options['dbpass'];
@@ -224,6 +222,9 @@ class OC_Setup {
 			}
 
 			if(count($error) == 0) {
+				OC_Appconfig::setValue('core', 'installedat',microtime(true));
+				OC_Appconfig::setValue('core', 'lastupdatedat',microtime(true));
+
 				//create the user and group
 				OC_User::createUser($username, $password);
 				OC_Group::createGroup('admin');

lib/updater.php

@@ -29,12 +29,12 @@ class OC_Updater{
 	 * Check if a new version is available
 	 */
 	public static function check(){
-		OC_Config::setValue('lastupdatedat',microtime(true));
+		OC_Appconfig::setValue('core', 'lastupdatedat',microtime(true));
 
 		$updaterurl='http://apps.owncloud.com/updater.php';
 		$version=OC_Util::getVersion();
-		$version['installed']=OC_Config::getValue( "installedat");
-		$version['updated']=OC_Config::getValue( "lastupdatedat");
+		$version['installed']=OC_Config::getValue('installedat');
+		$version['updated']=OC_Appconfig::getValue('core', 'lastupdatedat', OC_Config::getValue( 'lastupdatedat'));
 		$version['updatechannel']='stable';
 		$versionstring=implode('x',$version);