Scaling Issue

The stackImages() function didn't scale the image even after the 'scale' parameter being specified.

Just change this line:

```python
sizeW= imgArray[0][0].shape[1]
sizeH = imgArray[0][0].shape[0]
```

To:

```python
sizeW= int(imgArray[0][0].shape[1] * scale)
sizeH = int(imgArray[0][0].shape[0] * scale)
```

and remove the other scale variables