ncurses 5.6 - patch 20080906

+ corrected gcc options for building shared libraries on IRIX64.
+ add configure check for awk programs unable to handle big-strings,
  use that to improve the default for --enable-big-strings option.
+ makefile-fixes for --enable-weak-symbols (report by Frederic L W
  Meunier).
+ update test/configure script.
+ adapt ifdef's from library to make test/view.c build when mbrtowc()
  is unavailable, e.g., with HPUX 10.20.
+ add configure check for wcsrtombs, mbsrtowcs, which are used in
  test/ncurses.c, and use wcstombs, mbstowcs instead if available,
  fixing build of ncursew for HPUX 11.00