Description:
------------
SplMinHeap have the same behavior than SplMaxHeap when inserting data.
Top value of a SplMinHeap object is the max value instead of the min

Test script:
---------------
class MySimpleHeap extends SplMinHeap{
    public function  compare( $value1, $value2 ){
        return ( $value1 - $value2 );
    }
}

$obj = new MySimpleHeap();
$obj->insert( 8 );
$obj->insert( 0 );
$obj->insert( 4 );

foreach( $obj as $number ) {
    echo $number."\n";
}

// Output display : 8, 4, 0 instead of 0, 4, 8