ncurses 6.0 - patch 20150719

ncurses 6.0 - patch 20150719

+ correct an old logic error for %A and %O in tparm (report by "zreed").
+ improve documentation for signal handlers by adding section in the
  curs_initscr.3x page.
+ modify logic in make_keys.c to not assume anything about the size
  of strnames and strfnames variables, since those may be functions
  in the thread- or broken-linker configurations (problem found by
  Coverity).
+ modify test/configure script to check for pthreads configuration,
  e.g., ncursestw library.