FEATURE: fallback asset path for multi host setups

lib/tasks/assets.rake

@@ -175,11 +175,11 @@ task 'assets:precompile' => 'assets:precompile:before' do
     # protected
     manifest.send :save
 
-    if backup_path=ENV["BACKUP_ASSET_PATH"]
+    if GlobalSetting.fallback_assets_path.present?
       begin
-        FileUtils.cp_r("#{Rails.root}/public/assets/.", backup_path)
+        FileUtils.cp_r("#{Rails.root}/public/assets/.", GlobalSetting.fallback_assets_path)
       rescue => e
-        STDERR.puts "Failed to backup assets to #{backup_path}"
+        STDERR.puts "Failed to backup assets to #{GlobalSetting.fallback_assets_path}"
         STDERR.puts e
         STDERR.puts e.backtrace
       end