Consider adding labeled pictures of Cyton/Ganglion/WiFiShield to OpenBCI_GUI instructions

[produceconsumerobot]

After https://github.com/OpenBCI/Docs/blob/master/OpenBCI%20Software/01-OpenBCI_GUI.md#hardwaredriver-setup-for-openbci_gui-and-openbcihub
It might add clarity if there were labeled pictures of each board so people who were complete noobs and/or busy teachers had a refresher on the board naming jargon and help them cue into the relevant info for their specific board.

[retiutut]

Solution: Add one simple labeled picture with a Cyton, Ganglion, and a WiFi Shield.

Place the picture first in the section titled "Hardware/Driver Setup for OpenBCI_GUI and OpenBCIHub".

[leanneapichay]

Added the images to the doc and committed them.