More notifications and move start code to another file

src/history.rs

@@ -1,8 +1,7 @@
 use crate::data_provider::history::{get_history_of_set, HistoryItem};
 use crate::lang::{WordData, INVALID_ID};
-use crate::navigation::{NavigatedPage, Page};
+use crate::navigation::*;
 use crate::styling::*;
-use crate::{AppState, RootMessage};
 use chrono::Local;
 use iced::alignment::Horizontal::Center;
 use iced::widget::space::horizontal;
@@ -11,6 +10,7 @@ use iced::{Element, Fill, FillPortion, Task};
 use parking_lot::Mutex;
 use std::sync::Arc;
 use HistoryMessage::Back;
+use crate::app::AppState;
 
 #[derive(Clone)]
 pub struct HistoryState {