Status leds round2 (#1076)

Continuation of #802

Support RGB status LED to indicate:

Running/no-running
NT connected
At least one target visible

Configured by manually uploading hardware config JSON

photon-server/src/main/java/org/photonvision/Main.java

@@ -375,6 +375,7 @@ public class Main {
         }
 
         logger.info("Starting server...");
+        HardwareManager.getInstance().setRunning(true);
         Server.start(DEFAULT_WEBPORT);
     }
 }