merged types to StdClassGroup

src/stdtype.rs

@@ -7,3 +7,12 @@ pub struct StdType {
     pub abbrev: String,
     pub name: String,
 }
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "PascalCase")]
+pub struct StdClassGroup {
+    pub class_id: String,
+    pub id: String,
+    pub abbrev: String,
+    pub name: String,
+}