Moves some interface activities to the Swing thread.

We really should be doing this anyway.

interface/src/main/java/edu/regis/universeplayer/gui/Interface.java

@@ -561,19 +561,25 @@ public class Interface extends JFrame implements SongDisplayListener, ComponentL
 
     @Override
     public void updateSongs(Collection<? extends Song> songs)
+    {
+        SwingUtilities.invokeLater(() ->
         {
             this.songList.listAlbums(songs);
             this.centerView.setViewportView(this.songList);
             this.centerView.revalidate();
+        });
     }
 
     @Override
     public void updateCollections(CollectionType type, Collection<?> collections)
+    {
+        SwingUtilities.invokeLater(() ->
         {
             this.collectionList.listCollection(type, collections);
             this.centerView.setViewportView(this.collectionList);
             this.collectionList.revalidate();
             this.centerView.revalidate();
+        });
     }
 
     @Override
@@ -643,6 +649,8 @@ public class Interface extends JFrame implements SongDisplayListener, ComponentL
     @Override
     public <T> void onUpdate(DataProvider<T> provider, int updated,
                              int totalUpdate, String updating)
+    {
+        SwingUtilities.invokeLater(() ->
         {
             this.controls.setUpdateProgress(updated, totalUpdate, updating);
             if (updated == totalUpdate || totalUpdate == 0)
@@ -656,6 +664,7 @@ public class Interface extends JFrame implements SongDisplayListener, ComponentL
                  */
                 this.updateSongs(songs);
             }
+        });
     }
 
     @Override