fix bug in del tower and some ui changes

ad_graphics.cpp

@@ -181,3 +181,13 @@ void AD_Graphics::mouseMoveEvent(QMouseEvent *event)
     focus_item = 0;
 }
 
+void AD_Graphics::alienKilled(int id)
+{
+    if (select_al != 0) if (select_al->id() == id) select_al = 0;
+    QPainter p(mapimg);
+    p.translate((core->addata->aliens->curAliens[id].pos+QPointF(0.5,0.5))*cellSize);
+    p.drawImage(core->addata->bloodrect, *(core->addata->blood));
+    p.end();
+    resetCachedContent();
+}
+