message.py: MessagesType.SKIPPED added

buildstream/_frontend/widget.py

@@ -160,6 +160,7 @@ class TypeName(Widget):
         MessageType.START: "blue",
         MessageType.SUCCESS: "green",
         MessageType.FAIL: "red",
+        MessageType.SKIPPED: "yellow",
         MessageType.ERROR: "red",
         MessageType.BUG: "red",
     }

buildstream/_message.py

@@ -36,6 +36,7 @@ class MessageType():
     START = "start"        # Status start message
     SUCCESS = "success"    # Successful status complete message
     FAIL = "failure"       # Failing status complete message
+    SKIPPED = "skipped"
 
 
 # Messages which should be reported regardless of whether