feat: implement notification badge using markers from @sk22.

Thank you a lot man! This improvement is amazing

mastodon/src/main/java/org/joinmastodon/android/events/AllNotificationsSeenEvent.java

@@ -0,0 +1,4 @@
+package org.joinmastodon.android.events;
+
+public class AllNotificationsSeenEvent {
+}

mastodon/src/main/java/org/joinmastodon/android/events/NotificationReceivedEvent.java

@@ -0,0 +1,8 @@
+package org.joinmastodon.android.events;
+
+public class NotificationReceivedEvent {
+	public String id;
+	public NotificationReceivedEvent(String id) {
+		this.id = id;
+	}
+}