Bugfix: if the user set and them unset tile size, update the value even when it's unset

src/com/sheepit/client/standalone/swing/activity/Settings.java

@@ -491,6 +491,9 @@ public class Settings implements Activity {
 					System.exit(2);
 				}
 			}
+			else {
+				config.setTileSize(-1); // no tile
+			}
 			
 			parent.setCredentials(login.getText(), new String(password.getPassword()));