Add EventHub, add fav, reblog events, improve timelines (#562)

* Add AppStore, add fav, reblog events

* Add events, add handling to Timeline

* Add event handling to Notifications

* Mostly finish events

* Fix unsubscribing

* Cleanup timeline

* Fix newStatusEvent in thread, fix deleteEvent

* Insert new toots only in specific timelines

* Add missing else

* Rename AppStore to EventHub

* Fix tests

* Use DiffUtils for timeline

* Fix empty timeline bug. Improve loading placeholder

* Fix AsyncListDiff, loading indicator, "load more"

* Timeline fixes & improvements.

Fix infinite loading. Remove spinner correctly.
Don't refresh timeline without need.

app/src/main/java/com/keylesspalace/tusky/interfaces/AdapterItemRemover.java

@@ -1,21 +0,0 @@
-/* Copyright 2017 Andrew Dawson
- *
- * This file is a part of Tusky.
- *
- * This program is free software; you can redistribute it and/or modify it under the terms of the
- * GNU General Public License as published by the Free Software Foundation; either version 3 of the
- * License, or (at your option) any later version.
- *
- * Tusky is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
- * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
- * Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with Tusky; if not,
- * see <http://www.gnu.org/licenses>. */
-
-package com.keylesspalace.tusky.interfaces;
-
-public interface AdapterItemRemover {
-    void removeItem(int position);
-    void removeAllByAccountId(String accountId);
-}