Introduce new model `AccountItem`
Use `AccountItemList#create`
Inlination `Account#saveNewItem`
Improve using `_.first`
Add `Account#_save`
Overwrite `Account#save`
Modify attributes of `Account#doSave`
Remove unnecessary variables from `Account#save`
Stop recursive call at `Account#save`
Extract new function in `Account#save`
Inline `Account#doSave`
Reverse condition
improve
Merge branch 'refactoring/introduce-account-item'