ncurses 5.6 - patch 20070203

ncurses 5.6 - patch 20070203

+ modify fix_wchnstr() in form library to strip attributes (and color)
  from the cchar_t array (field cells) read from a field's window.
  Otherwise, when copying the field cells back to the window, the
  associated color overrides the field's background color (report by
  Ricardo Cantu).
+ improve tracing for form library, showing created forms, fields, etc.
+ ignore --enable-rpath configure option if --with-shared was omitted.
+ add _nc_leaks_tinfo(), _nc_free_tic(), _nc_free_tinfo() entrypoints
  to allow leak-checking when both tic- and tinfo-libraries are built.
+ drop CF_CPP_VSCAN_FUNC macro from configure script, since C++ binding
  no longer relies on it.
+ disallow combining configure script options --with-ticlib and
  --enable-termcap (report by Rong-En Fan).
+ remove tack from ncurses tree.