Remember LED sign colors

[jerrylee17]

Health check needs to pass LED sign current color

[hsorathia]

me do

[evanugarte]

3/2 Meeting

1. Add a function to the LedSignServicer class that saves the fields sent from the website.
2. Merge the HealthCheckResponse proto and LedSignRequest proto into LedSignRecord. You will also need to modify the RPC services up top.