内容のチェックが必要。ユーザー名とリポジトリ名の間に半角スペース入った状態でプロジェクトを保存し、チケットを追加しようとするとエラー。

```
URI::InvalidURIError (bad URI(is not URI?): /repos/kmiyake / timecard-rails/issues):
  app/models/project_github.rb:10:in `add_issue'
  app/controllers/issues_controller.rb:30:in `block in create'
  app/controllers/issues_controller.rb:27:in `create'


  Rendered /Users/kotamiyake/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dispatch/middleware/templates/rescues/_source.erb (0.7ms)
  Rendered /Users/kotamiyake/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dispatch/middleware/templates/rescues/_trace.erb (1.3ms)
  Rendered /Users/kotamiyake/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dispatch/middleware/templates/rescues/_request_and_response.erb (2.2ms)
  Rendered /Users/kotamiyake/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/gems/actionpack-4.0.0/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb within rescues/layout (16.8ms)
```