Make enable method name consistent on TTL field

Author: russcam

src/Nest/Mapping/MetaFields/Ttl/TtlField.cs

@@ -18,14 +18,14 @@ public class TtlField : ITtlField
 		public Time Default { get; set; }
 	}
 
-	public class TtlFieldDescriptor 
+	public class TtlFieldDescriptor
 		: DescriptorBase<TtlFieldDescriptor, ITtlField>, ITtlField
 	{
 		bool? ITtlField.Enabled { get; set; }
 		Time ITtlField.Default { get; set; }
 
-		public TtlFieldDescriptor Enable(bool enable = true) => Assign(a => a.Enabled = enable);
+		public TtlFieldDescriptor Enabled(bool enabled = true) => Assign(a => a.Enabled = enabled);
 
 		public TtlFieldDescriptor Default(Time defaultTtl) => Assign(a => a.Default = defaultTtl);
 	}
-}
+}