Use strong paramaters intead of raw params
Refactor code

検索関連の操作はscopeに定義する。
Add feature of continuing add issue

fix #380
Fix incorrect code
Include enabled_github paramater as part of issue_params
Add test and rename method
Merge pull request #394 from kmiyake/iss-380_feature_of_continuing_to_add_issue

Add feature of continuing to add issue