ncurses 5.9 - patch 20130105

+ add "-s" option to test/view.c to allow it to start in single-step
  mode, reducing size of trace files when it is used for debugging
  MinGW changes.
+ revert part of 20121222 change to tinfo_driver.c
+ add experimental logic in win_driver.c to improve optimization of
  screen updates.  This does not yet work with double-width characters,
  so it is ifdef'd out for the moment (prompted by report by Erwin
  Waterlander regarding screen flicker).