+ quiet some pedantic gcc warnings.
+ modify _nc_wgetch() to check for a -1 in the fifo, e.g., after a
SIGWINCH, and discard that value, to avoid confusing application
(patch by Eygene Ryabinkin, FreeBSD bin/136223).
+ remove wide-character checks from unctrl() (patch by Clemens Ladisch).
+ revise wadd_wch() and wecho_wchar() to eliminate dependency on
unctrl().
+ continue integrating "sp-funcs" by Juergen Pfeifer (incomplete).
+ add configure script --enable-sp-funcs to enable the new set of
extended functions.
+ start integrating patches by Juergen Pfeifer:
+ add extended functions which specify the SCREEN pointer for several
curses functions which use the global SP (these are incomplete;
some internals work is needed to complete these).
+ add special cases to configure script for MinGW port.
