partial subscriptions

not really partial. they just happen per peripheral now

telemetry/rpm_lights.go

@@ -1,5 +1,7 @@
 package telemetry
 
+import "esdi/constants"
+
 type RPMLights struct {
 	State string
 }
@@ -28,3 +30,7 @@ func (rl *RPMLights) Process(td *TelemetryData) {
 func (rl *RPMLights) EnsureSubscribed() []FieldID {
 	return []FieldID{RPM}
 }
+
+func (rl *RPMLights) Name() string {
+	return constants.RPMLightsName
+}