ncurses: update to 6.0 and rename 5.9 to ncurses-compat v3

ncurses: update to 6.0 and rename 5.9 to ncurses-compat v3

This patch updates the ncurses to 6.0. The old 5.9 are renamed to ncurses-compat.
The compat makes the old libs maintainable and the compat rootfile is cleaned up.
The 6.0 is build after 5.9 and all IPFire componentes will build with 6.0
In version 6 only the wide-character libraries are build. The are usable
in both multibyte and traditional 8-bit locales while normal libraries work
properly only in 8-bit locales. The toolchain is only bild with 6.0.

Signed-off-by: Marcel Lorenz <marcel.lorenz@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>