remove turbolinks
add bootstrap-sass for bootstrap
add mysql2 gem
use slim template
Merge pull request #17 from songjiayang/issue_12

[#12] 引入bootstrap,mysql2,slim
添加NEWS.md
Merge pull request #19 from songjiayang/issue_18

[#18] 添加NEWS.md
Update NEWS.md
添加.travis.yml
Merge pull request #21 from songjiayang/issue_19

[#19]添加.travis.yml
merge master code