disable cal-china-x calendar utils for Org-mode Agenda buffer insert diary entry with English format instead of Chinese format.
improve bbdb init file comments.
improve mu4e init.
enable org-bbdb module for Org-mode.
change org-diary entry face in Agenda buffer.
improve Org-mode init file comments. with some init config examples.
improve Emacs Lisp mode template snippet to use buffer name in comment annotation.
many minor improves.
let visual-regexp use Emacs built-in regexp engine 'emacs.
add crontab-mode into auto-mode-alist.
let auto-complete quick help popup prefer use pos-tip. It will replace popup.el, does not have wrap issue.