Updated group-related events and exceptions.

briar-api/src/org/briarproject/api/event/GroupAddedEvent.java

@@ -0,0 +1,17 @@
+package org.briarproject.api.event;
+
+import org.briarproject.api.sync.Group;
+
+/** An event that is broadcast when a group is added. */
+public class GroupAddedEvent extends Event {
+
+	private final Group group;
+
+	public GroupAddedEvent(Group group) {
+		this.group = group;
+	}
+
+	public Group getGroup() {
+		return group;
+	}
+}