fdo#81182: glTF window size does not match with the scene size after resizing

When viewport changed it is necessary to resize the whole scene.
Calling releasFbo removes size dependent objects and triggers
creating the new ones with the new size.

Change-Id: Ibd8be1e92be92da31add4a30aa799f0995b1cc88
fdo#81182: Resizing glTF window affects camera position

Camera moves by click and drag, with checking the last mouse
position we can make sure click was done inside the window
before drag.
Resizing can trigger drag event, but not click event.

Change-Id: I9e8b70fcb4a0abf26e76e03cafd026f940eceb10