Problem:    Clearing a pointer takes two lines.
Solution:   Add VIM_CLEAR() and replace vim_clear(). (Hirohito Higashi,
            closes #2629)

Problem:    Modelines in source code are inconsistant.
Solution:   Use the same line in most files.  Add 'noet'.  (Naruhiko Nishino)

Problem:    Using old style function declarations.
Solution:   Change to new style function declarations. (script by Hirohito
            Higashi)

Problem:    Users are not aware their encryption is weak.
Solution:   Give a warning when prompting for the key.

Problem:    Windows 64 bit compiler warnings.
Solution:   Add type casts. (Mike Williams)

Problem:    Encryption implementation is messy.  Blowfish encryption has a
            weakness.
Solution:   Refactor the encryption, store the state in an allocated struct
            instead of using a save/restore mechanism.  Introduce the
            "blowfish2" method, which does not have the weakness and encrypts
            the whole undo file. (largely by David Leadbeater)