Search amazon items and create new toybox

## Add user story:
- User searches amazon items and click it. Clicked items are appended to new box form. 
- User inputs title and description of box.
- User register new box and see it.

## Refactor some features:
- Modify DB cleaner configures.
- Remove unnecessary requirement or include mock modules.
- Add signup user mock for feature spec.

@okawa14all 
please have a look!