Enable Marketplace for Flipper (#3491)

Summary:
This is PR on top of: https://github.com/facebook/flipper/pull/3473

It adds an option to Settings to allow distribution of marketplace plugins.

Also includes a simple fetch function to retrieve data from external API/server.

## Changelog

Allow marketplace plugins

Pull Request resolved: https://github.com/facebook/flipper/pull/3491

Test Plan:
1. Enable marketplace
2. Provide custom marketplace server (it will serve the list of internal plugins with downloadURL)
3. Test if can see Available plugins and can download/remove the plugin
4. If new update for the plugin, it should also allow auto update

Reviewed By: antonk52

Differential Revision: D34586339

Pulled By: nikoant

fbshipit-source-id: c887982aa0f0f9abd3b5360f22e8692a2445d345

desktop/flipper-ui-core/src/dispatcher/handleOpenPluginDeeplink.tsx

@@ -320,7 +320,7 @@ async function verifyPluginStatus(
   if (!isTest() && !store.getState().plugins.marketplacePlugins.length) {
     // plugins not yet fetched
     // updates plugins from marketplace (if logged in), and stores them
-    await loadPluginsFromMarketplace();
+    await loadPluginsFromMarketplace(store);
   }
   // while true loop; after pressing install or add GK, we want to check again if plugin is available
   while (true) {