Add "Media" tab for rooms (#196)

* WIP on Media tab to rooms

* handle error for downloadFile if it's missing

* Add warning message for rooms Media tab

* Fix error message for download media of rooms

* update readme

src/Context.tsx

@@ -0,0 +1,7 @@
+import { createContext, useContext } from "react";
+
+import { Config } from "./utils/config";
+
+export const AppContext = createContext<Config>({} as Config);
+
+export const useAppContext = () => useContext(AppContext) as Config;