Android java classes code cleanup.

Source/Android/src/com/googlecode/urho3d/Urho3D.java

@@ -1,14 +1,5 @@
 package com.googlecode.urho3d;
 
 import org.libsdl.app.SDLActivity;
-import android.os.*;
 
-public class Urho3D extends SDLActivity {
-    protected void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-    }
-
-    protected void onDestroy() {
-        super.onDestroy();
-    }
-}
+public class Urho3D extends SDLActivity {}

Source/Android/src/org/libsdl/app/SDLActivity.java

@@ -923,4 +923,3 @@ class SDLInputConnection extends BaseInputConnection {
     public native void nativeSetComposingText(String text, int newCursorPosition);
 
 }
-