Big Reconstruction

* Creat a switch for each major mode, and put the switches into init.el.
* Move all major modes into the newly created directory site-lisp/.
* Remove "custom-set-variables" part in the file init.el.
* Put most of the variables setting statement into setq-default clause of the file site-lisp/init-editing-utils.el
Wrong Function Call Fixed

Change (wk-misc-custom-init) to (wk-misc-init) to make the function call work.
Disable Emacs's Builtin Version Control Functionality

* Delete the directory lisp/.svn/
* Add "vc-handled-backends nil" to "setq-default" in the file lisp/init-editing-utils.el to disable Emacs's builtin version control.
Disable auto-complete automatically

Change to:
       Pressing TAB to invoke auto-complete.
1. add some support for cc-mode;
2. add google-c-style.el;
3. remove electric-paren from init-editing.
1. update auctex from 11.87.2 to 11.87.7
2. delete w3m and weibo plugins
3. change c-set-style to K&R and the indentation character from spaces to tab
1. modify .gitignore to deny files with a trailing ~(tilde).
2. update exec-path-from-shell functionality.
1. modify .gitignore file to not accept elpa packages
1. modify the auto-complete configuration to give a highlight when completing.
Add the xcscope extension for C/C++ code exploring.
Add hs-minor-mode to c-code-common-hook, and bind the F7 key to hs-toggle-hiding