Incorrect interaction of slk_init and ripoffline

[Clive Nicolson]

In ncurses (at least version 5.5):

slk_init behaves as if it has been called after all calls to ripoffline, when
it emulates slk's. I would have expected it to have reserved a line before
any lines reserved by calls to ripoffline. This means that the slk line may
not be on the bottom of the screen.

Documentation for some versions of curses say that slk_init must be called
before ripoffline. slk_init on curses under OpenSolaris appears to reserve a
line before any reserved by ripoffline.

Clive