Google Cardboard Magnet Holder

The magnet holder slots in my [google cardboard](https://cardboard.withgoogle.com/) kit were on the wrong side for my phone, when I pulled down the magnet, it didn't register a "click" on the phone because the phone's compass was on the other side.

This holder can be glued to the cardboard kit to hold the magnet on the other side, where it can be read properly by the phone.