includePluginの呼び出し元はincludeEthnaPluginただ一か所だったので、場合分けは不要。
includePluginの呼び出し元はincludeEthnaPluginただ一か所だったので、$app_id渡す必要なし。
refactor: rename includePlugin -> import (as is develop branch)
refactor
refactor
remove includeEthnaPlugin