Merge pull request #281 from VacuumBreather/train_speed_adaptation

# Conflicts:
#	src/saveload/extended_ver_sl.cpp
#	src/saveload/extended_ver_sl.h

src/date.cpp

@@ -39,6 +39,8 @@ YearMonthDay _game_load_cur_date_ymd;
 DateFract _game_load_date_fract;
 uint8 _game_load_tick_skip_counter;
 
+extern void ClearOutOfDateSignalSpeedRestrictions();
+
 /**
  * Set the date.
  * @param date  New date
@@ -283,6 +285,7 @@ static void OnNewDay()
 		SetWindowWidgetDirty(WC_STATUS_BAR, 0, WID_S_LEFT);
 	}
 	EnginesDailyLoop();
+	ClearOutOfDateSignalSpeedRestrictions();
 
 	/* Refresh after possible snowline change */
 	SetWindowClassesDirty(WC_TOWN_VIEW);