simplify status type declaration

- StatusType: simpler inheritance (inherit from module instead of Enum)
- StatusType: more robust for standard codes, give names only
- <Module>.Status is automatically extended
- Enum: accept duplicates with same name and value

Change-Id: Iad1dacf14c31fe6f4ae48e7560b29e49838e4f23
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/30716
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

test/test_lib_enum.py

@@ -83,3 +83,12 @@ def test_Enum_bool():
     e = Enum('OffOn', off=0, on=1)
     assert bool(e(0)) is False
     assert bool(e(1)) is True
+
+
+def test_Enum_duplicate():
+    e = Enum('x', a=1, b=2)
+    Enum(e, b=2, c=3)  # matching duplicate
+    with pytest.raises(TypeError):
+        Enum(e, b=3, c=4)  # duplicate name with value mismatch
+    with pytest.raises(TypeError):
+        Enum(e, c=1)  # duplicate value with name mismatch