Protobuf communication

[ajayyy]

• Get protobuf compiling
• Get COBS decoding
• Decode with TCP
• Support not using COBS for button box
• COBS shouldn't apply to RSSI messages, and it's delimeter still needs to be \n
• Test COBS decoding
• Decode with Serial
• Create simple proto file to test
• Decode protobuf to string (protobuf object is just wrapping the current string for now)