Launcher3删除开机引导页面

修改方案如下：
请定位到src/com/android/launcher3/LauncherClings.java文件：

class LauncherClings implements OnClickListener {
......
private static final String TAG_CROP_TOP_AND_SIDES = "crop_bg_top_and_sides
- private static final boolean DISABLE_CLINGS = false;
+ private static final boolean DISABLE_CLINGS = true;