ncurses 6.0 - patch 20160220

ncurses 6.0 - patch 20160220

+ modify test/configure script to check for pthread dependency of
  ncursest or ncursestw library when building ncurses examples, e.g.,
  in case weak symbols are used.
+ modify configure macro for shared-library rules to use -Wl,-rpath
  rather than -rpath to work around a bug in scons (FreeBSD #178732,
  cf: 20061021).
+ double-width multibyte characters were not counted properly in
  winsnstr and wins_nwstr (report/example by Eric Pruitt).
+ update config.guess, config.sub from
	http://git.savannah.gnu.org/cgit/config.git