Deprecate scope from entity (#108)

diff --git a/metrics-v2.graphqls b/metrics-v2.graphqls
index 35be22d..091ba42 100644
--- a/metrics-v2.graphqls
+++ b/metrics-v2.graphqls
@@ -34,13 +34,14 @@
 }
 
 input Entity {
-    # 1. scope=All, no name is required.
-    # 2. scope=Service, ServiceInstance and Endpoint, set necessary serviceName/serviceInstanceName/endpointName
-    # 3. Scope=ServiceRelation, ServiceInstanceRelation, EndpointRelation and ProcessRelation
+    # Deprecated from 9.4.0
+    # Scope could be sensed automatically through given metric name.
+    scope: Scope
+    # 1. metrics Scope=Service, ServiceInstance and Endpoint, set necessary serviceName/serviceInstanceName/endpointName
+    # 2. metrics Scope=ServiceRelation, ServiceInstanceRelation, EndpointRelation and ProcessRelation
     #    serviceName/serviceInstanceName/endpointName/processName is/are the source(s)
     #    destServiceName/destServiceInstanceName/destEndpointName/destProcessName is/are destination(s)
     #    set necessary names of sources and destinations.
-    scope: Scope!
     serviceName: String
     # Normal service is the service having installed agent or metrics reported directly.
     # Unnormal service is conjectural service, usually detected by the agent.