The former allows the ncurses (and pdcurses) macros getsyx and setsyx
to be implemented, which is needed by a surprising number of applications.
The latter is needed for Python curses support so it doesn't have to dive
into ncurses window structure.
* Added code to __restartwin to restore meta and cursor visibility states
* Added code to __stopwin to disable meta.
* Added the *line group of functions for drawing character lines.
(this is a requirement of SUSv2) - the old macro behaviour can be
restored by defining _CURSES_USE_MACROS.
Changed function prototypes to use ANSI style.
All externally visible functions now have ANSI style declarations.
