Greatly optimize weather updates.

1Weather/Model/LocationManager.swift

@@ -53,6 +53,7 @@ public class LocationManager {
             self?._locations = locations
             self?._selectedLocationIndex = selectedIndex
             self?.handleLocationsChange(locationsChanged: true, selectedLocationChanged: true)
+            self?.updateAllWeatherIfNeeded()
         }
     }
     
@@ -72,7 +73,6 @@ public class LocationManager {
             }
         }
         storage.save(locations: locations, selectedIndex: selectedLocationIndex)
-        updateAllWeatherIfNeeded()
     }
     
     public private(set) var locations: [Location] {
@@ -354,6 +354,7 @@ public class LocationManager {
                 selectedLocationIndex = locations.count - 1
             }
         }
+        updateAllWeatherIfNeeded()
     }
     
     public func addIfNeeded(partialLocation: PartialLocation, selectLocation: Bool) {