0.0.50.beta20 pre

- 修复了 issues:468 提到的首次使用 WaitDialog 展示进度时 progress 不能设为 0 的问题；
- BottomDialog 提供了对外暴露的 boxBody（对话框内容布局外层）实例；
- WindowUtil 提供了额外自定义WindowManager.LayoutParams的接口：

```java
WindowUtil.windowSettings = new WindowUtil.WindowSettings() {
    @Override
    public WindowManager.LayoutParams overrideWindowLayoutParamsInterface(Context context, View dialogView, WindowManager.LayoutParams originWindowLayoutParams) {
        //处理 originWindowLayoutParams...
        return originWindowLayoutParams;
    }
};
```

- 修复Window模式下，多层Dialog触摸事件逐级向下层传递的问题；

DialogX/src/main/java/com/kongzue/dialogx/dialogs/WaitDialog.java

@@ -472,7 +472,7 @@ public class WaitDialog extends BaseDialog {
             onDialogInit();
         }
 
-        private float oldProgress;
+        private float oldProgress = -1;
 
         public void refreshView() {
             if (boxRoot == null || getOwnActivity() == null) {

DialogX/src/main/java/com/kongzue/dialogx/util/WindowUtil.java

@@ -36,7 +36,7 @@ public class WindowUtil {
         public abstract WindowManager.LayoutParams overrideWindowLayoutParamsInterface(Context context, View dialogView, WindowManager.LayoutParams originWindowLayoutParams);
 
         //自定义根布局
-        public abstract ViewGroup overrideRootView(Context context);
+        public ViewGroup overrideRootView(Context context){return null;};
     }
 
     //自定义window设置

app/release/output-metadata.json

@@ -12,7 +12,7 @@
       "filters": [],
       "attributes": [],
       "versionCode": 49,
-      "versionName": "0.0.50.beta14",
+      "versionName": "0.0.50.beta19",
       "outputFile": "app-release.apk"
     }
   ],

app/src/main/java/com/kongzue/dialogxdemo/activity/MainActivity.java

@@ -75,6 +75,7 @@ import com.kongzue.dialogx.interfaces.MenuItemTextInfoInterceptor;
 import com.kongzue.dialogx.interfaces.OnBackPressedListener;
 import com.kongzue.dialogx.interfaces.OnBackgroundMaskClickListener;
 import com.kongzue.dialogx.interfaces.OnBindView;
+import com.kongzue.dialogx.interfaces.OnBindingView;
 import com.kongzue.dialogx.interfaces.OnDialogButtonClickListener;
 import com.kongzue.dialogx.interfaces.OnIconChangeCallBack;
 import com.kongzue.dialogx.interfaces.OnInputDialogButtonClickListener;
@@ -602,7 +603,6 @@ public class MainActivity extends BaseActivity {
                     }
                 });
                 WaitDialog.dismiss(3000);
-
             }
         });
 
@@ -852,7 +852,7 @@ public class MainActivity extends BaseActivity {
                     public void onBind(MessageDialog dialog, View v) {
 
                     }
-                });
+                }).setMaskColor(Color.TRANSPARENT);
             }
         });