ncurses 6.1 - patch 20180818

ncurses 6.1 - patch 20180818

+ build-fix for PDCurses with ncurses-examples.
+ improved CF_CC_ENV_FLAGS.
+ modify configure scripts to reduce relinking/ranlib during library
  install (Debian #903790):
  + use "install -p" when available, to avoid need for ranlib of
    static libraries.
  + modify scripts which use "--disable-relink" to add a 1-second
    sleep to work around tools which use whole-second timestamps, e.g.,
    in utime() rather than the actual file system resolution.
+ add "--disable-touching" option for using "install -p" option during
  the install, e.g., so that header-files have a predictable timestamp.