add script to build tables
add default values to news table
drop table before creating
add readme
add a script to create news_raw tables for 12 months
Merge pull request #12 from kiang/master

加入建立資料表的程式與調整部份欄位
Merge github.com:ronnywang/newsdiff into merge_upstream

Conflicts:
	webdata/stdlibs/url-normalizer.js
Ugly hack for MySQL table creations

1. Add 'longtext' type support.
2. Add DEFAULT CHARSET=utf8mb4 to all table creation queries.
Merge pull request #13 from yookoala/merge_upstream

Merge upstream