Add ImageRun feature

src/patcher/content-types-manager.ts

@@ -0,0 +1,16 @@
+import { Element } from "xml-js";
+
+import { getFirstLevelElements } from "./util";
+
+export const appendContentType = (element: Element, contentType: string, extension: string): void => {
+    const relationshipElements = getFirstLevelElements(element, "Types");
+    // eslint-disable-next-line functional/immutable-data
+    relationshipElements.push({
+        attributes: {
+            ContentType: contentType,
+            Extension: extension,
+        },
+        name: "Default",
+        type: "element",
+    });
+};