给 ivy-occur 添加再次过滤的功能

[casouri]

icomplete里有时候prompt会消失，你有遇到吗？如图，C-x C-f补全路径，prompt和前面的路径会消失，C-a到行首才能看到。配置用了你的

(progn
  (setq icomplete-prospects-height 20)
  (setq icomplete-delay-completions-threshold 0)
  (setq icomplete-max-delay-chars 0)
  (setq icomplete-delay-completions-threshold 2000)
  (setq icomplete-compute-delay 0)
  (setq icomplete-show-matches-on-no-input t)
  (setq icomplete-hide-common-prefix nil)
  (setq icomplete-separator "\n")
  (setq icomplete-with-completion-tables t)
  (setq icomplete-in-buffer t)
  (setq icomplete-tidy-shadowed-file-names t))