ncurses 6.1 - patch 20180210

ncurses 6.1 - patch 20180210

+ modify misc/Makefile.in to install/uninstall explicit list in case
  the build-directory happens to have no ".pc" files when an uninstall
  is performed (report by Jeffrey Walton).
+ deprecate safe-sprintf, since the vsnprintf function, which does what
  was needed, was standardized long ago.
+ add several development/experimental options to development packages.
+ minor reordering of options in configure script to make the threaded
  and reentrant options distinct from the other extensions which are
  normally enabled.