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

Problem:    Cannot make Vim fail on an internal error.
Solution:   Add IEMSG() and IEMSG2(). (Domenique Pelle)  Avoid reporting an
            internal error without mentioning where.

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

Problem:    Looping over windows, buffers and tab pages is inconsistant.
Solution:   Use FOR_ALL_ macros everywhere. (Yegappan Lakshmanan)

Problem:    There is still code and help for unsupported systems.
Solution:   Remove the code and text. (Hirohito Higashi)

Problem:    On MS-Windows large files (> 2Gbyte) cause problems.
Solution:   Use "off_T" instead of "off_t".  Use "stat_T" instead of "struct
            stat".  Use 64 bit system functions if available.  (Ken Takata)

Problem:    The MS-DOS code does not build.
Solution:   Remove the old MS-DOS code.

Problem:    Warning for not using return value of fcntl().
Solution:   Explicitly ignore the return value.

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

Problem:    Still using __ARGS.
Solution:   Remove __ARGS in several files. (script by Hirohito Higashi)
            Also remove use of HAVE_STDARG_H.