Revision 1647867

- Support for Office Binary Document RC4 CryptoAPI Encryption for HSLF
- Support for Office Binary Document RC4 Encryption
- use LittleEndian class in LittleEndianInputStream
- add normalize method for HSLF, to remove edit history, which is also necessary for encryption support
- update PersistDirectoryEntry handling in PersistPtrHolder to recognize groups while serializing
- deprecated PersistPtrHolder.getSlideOffsetDataLocationsLookup() - throws now UnsupportedOperationException,
  as this wasn't used outside the scope of the class and was quite internal logic of PersistPtrHolder