Tag "safe to remove" added to unused packages;

OpenCV Manager version++.

android/service/engine/AndroidManifest.xml

 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="org.opencv.engine"
-    android:versionCode="23@ANDROID_PLATFORM_VERSION_CODE@"
-    android:versionName="2.3" >
+    android:versionCode="24@ANDROID_PLATFORM_VERSION_CODE@"
+    android:versionName="2.4" >
 
     <uses-sdk android:minSdkVersion="@ANDROID_NATIVE_API_LEVEL@" />
     <uses-feature android:name="android.hardware.touchscreen" android:required="false"/>

android/service/engine/src/org/opencv/engine/manager/ManagerActivity.java

@@ -358,6 +358,8 @@ public class ManagerActivity extends Activity
                     else
                     {
                         temp.put("Activity", "n");
+                        if (!PublicName.equals("Built-in OpenCV library"))
+                            Tags = "safe to remove";
                     }
                 }
                 else