Merge branch 'master' of https://github.com/liangxiaobo/tang into liangxiaobo-master

Conflicts:
	protected/views/layouts/main-tang.php
修改user表extension_user_id字段类型；vote表添加create_datetime字段
Merge branch 'master' of http://github.com/liuwanwei/tang
Merge pull request #45 from maoyu/master

修改user表extension_user_id字段类型；vote表添加create_datetime字段
为datetime类型设置current_timestamp默认值时，在低版本mysql会有问题，将类型修改为TIMESTAMP
Merge pull request #46 from maoyu/master

为datetime类型设置current_timestamp默认值时，在低版本mysql会有问题，将类型修改为TIMESTAMP
修改首页右侧最近评论的图片与内容的对齐