use pkg-config to locate ncurses rather than a library search

--- a/configure.in
+++ b/configure.in
@@ -19,14 +19,9 @@
 AC_HEADER_STDC
 AC_PROG_GCC_TRADITIONAL
 
-AC_CHECK_HEADERS(ncurses.h)
-if test "$ac_cv_header_ncurses_h" = "no"; then
-  AC_CHECK_HEADERS(curses.h)
-  if test "$ac_cv_header_curses_h" = "no"; then
-    echo "*** Cannot find Curses headers, probably not installed"
-    echo "*** Hexedit will not run without the curses library"
-  fi
-fi
+PKG_CHECK_MODULES(NCURSES, ncurses)
+CFLAGS="$CFLAGS $NCURSES_CFLAGS -DHAVE_NCURSES_H=1"
+LIBS="$LIBS $NCURSES_LIBS"
 
 AC_CHECK_HEADERS(fcntl.h getopt.h limits.h sys/ioctl.h unistd.h)
 AC_HEADER_DIRENT
@@ -96,11 +91,4 @@ else
   fi
 fi
 
-AC_CHECK_LIB(ncurses, newwin, ,
-    AC_CHECK_LIB(curses, newwin), ,
-    echo "Hexedit requires the curses library"
-    echo "Ncurses is freely available: ftp://ftp.gnu.org/pub/gnu/"
-    exit 1)
-
-
 AC_OUTPUT(Makefile docs/Makefile gnu/Makefile src/Makefile)