Tombstone Matrix Stake

This is an alternate bracket for the Adafruit Matrix Portal to allow it to be staked in the ground in a portrait orientation. This is intended to be used with the Adafruit Tombstone Matrix Portal project. I wanted to be able to stake the Matrix Portal into the ground separately from the tombstone, as my tombstone styrofoam prop would not be sturdy enough to support the weight of the matrix portal hanging off the back of it.