correct get Progress sum / #3760

from class_project.inc.php

  /**
    * get Progress sum
    */
    function getProgressSum()
    {

        $sum=0;
        if($tasknum = $this->getNumTasks()) {
			if($tasksum = $this->getSumTasksProgress()) {
			//$sum=$tasksum/$tasknum*100;
			$sum=($tasksum/$tasknum*100)/100;
			}
        }
        return $sum;
    }