QuantileFilter updated (still needs to be moved in the corresponding imglib package)

Rewrite of the old QuantileFilter, bug is fixed and also it runs (marginally) faster now. 

In the attachment are two pictures which show the results of the Image Calculator if the results of the old and new Quantile Filter are subtracted from each other. It can be clearly seen that the old Quantile Filter ignored the border of the image and also that the are no differences in the middle between the two versions.


![result](https://f.cloud.github.com/assets/4389187/1949547/8ddb0e40-810f-11e3-9172-98ecfba8474e.PNG)
![result1](https://f.cloud.github.com/assets/4389187/1949548/9155bdfe-810f-11e3-8606-f825dd7080ae.PNG)