add target attribute
Rails 4.0.3
更正错别字，fixes #245
Merge pull request #274 from diguage/master

更正错别字，fixes #245
现在Grape API出错将返回简单的出错消息而不是庞大的Web错误界面, fixes #269
修复了api/v2/topics.json中依然出现了属于No Point节点的内容的Bug, fixes #275
Ruby 2.1.1
Merge pull request #276 from bachue/fix-275

修复了api/v2/topics.json中依然出现了属于No Point节点的内容的Bug, fixes #275
Merge pull request #270 from bachue/fix-269

现在API出错将返回简单的出错消息而不是庞大的Web错误界面, fixes #269
Merge pull request #271 from martinx/master

为markdown链接增加target属性,从新窗口打开.
Merge branch 'master' of github.com:ruby-china/ruby-china
修正注册页面 CSRF 的漏洞;
Fixed title field auto focus in topic form.
Add iOS 7.1 viewport : minimal-ui
Fix viewport.
Update copyright year
Conditional gem source

If USE_OFFICIAL_GEM_SOURCE is set then rubygems.org is used,
otherwise taobao.org mirror is used.
Try bundle with USE_OFFICIAL_GEM_SOURCE for travis
Set USE_OFFICIAL_GEM_SOURCE environment variable for travis
Update README about USE_OFFICIAL_GEM_SOURCE [ci skip]