init.el: Add setting of popup
init.el: Modify whitespace-display-mappings
init.el: Add set-minor-mode-string function
init.el: Modify minor-mode-alist using function
init.el: Modify minor-mode-alist
init.el: Modify ibuffer-mode-hook
init.el: Add setting of auto-complete-mode
init.el: Remove ac-use-comphist
init.el: Add advice to ac-comphist-init
init.el: Modify ibuffer-maybe-show-predicates