Description:
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Imagick::setImageOpacity() method is missing from Imagick 2.0.0

listing of get_class_methods('imagick');
does not show setImageOpacity()


Reproduce code:
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header('Content-type: image/jpeg');

$image1 = new Imagick('test1.jpg');
$image2 = new Imagick('test2.jpg');

$image2->setImageOpacity(0.7);

$image1->compositeImage($image2, Imagick::COMPOSITE_OVER, 0, 0);

echo $image1;

Expected result:
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Should display a composite of two images.

Actual result:
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Fatal error: Call to undefined method Imagick::setImageOpacity()