Establish protocols/format for transferring custom data between RPis and GCS

Custom data may include:
- Video streams from drones: it would be helpful to automatically modify the resolution and framerate of incoming video to adjust to available network bandwidth.
- RTSP commands to pause/resume video streams from different drones
- "Object-detected" messages from drones that may include video frames, and GPS locations

GCS program made by the Capstone team could be improved to handle this custom data.
Need to determine the best approach to receive all these streams of data. In the end, all this data should be accessed through GCS, but how should we send/receive all this data?