Improve the example "Displaying an image" for Android (Java)

[Paolo Brandoli]

On Android, the maximum memory size that can be allocated by the JM is 64 MB.

For larger images, this size is easily surpassed.

Instead of returning the whole buffer, get only portions of the rendered buffer from Imebra and then use Bitmap.setPixels to set portions of the destination image. The returned buffer must be re-packed as integer values instead of bytes.