- Fix "supplied argument is not a valid   Directory resource" error when calling rewind() - Add method isOpen()
- Fix "supplied argument is not a valid
  Directory resource" error when calling rewind()
- Add method isOpen()

git-svn-id: 526f3b90ad6d9b1dfe840af828070ca3d99521ac@7905 d2cacbed-c0f6-0310-851a-9dad52fc623a

johannes85/core