Revert "Don't use 'show paren' mode because it corrupts the virtual indentation of Org mode."

This reverts commit 23238e52654fe422be6b2bc6f7257d24fad959cb.
Add the path to the ddskk directory to load-path.
Put a large SKK dictionary.
Install 'ddskk' into ./site-lisp.
Add 'skk-autoloads.el' generated by make.