[WIP] Add FlatCache lib and use for Notifications (#632)

* init FlatCache lib

* tests for all other cases

* install flatcache to freeitme project, move VM creation into client

* refactor and split up inbox design

* fixup flatcache pod

Classes/Repository/RepositoryOverviewViewController.swift

@@ -54,6 +54,11 @@ ListAdapterDataSource {
         rz_smoothlyDeselectRows(collectionView: feed.collectionView)
     }
 
+    override func viewDidAppear(_ animated: Bool) {
+        super.viewDidAppear(animated)
+        feed.viewDidAppear(animated)
+    }
+
     override func viewWillLayoutSubviews() {
         super.viewWillLayoutSubviews()
         feed.viewWillLayoutSubviews(view: view)