Allow ImageTextButton to have image and label on separate rows

[pyko]

ImageTextButton allows you to create button where the image and label are on the same row (image left, label right).

Added functionality to allow the image and label to be on separate rows (image top, label below)

[NathanSweet]

You can do this outside of the ImageTextButton:

button.clearChildren();
button.add(button.getImage()).row();
button.add(button.getLabel());

I think I prefer this over making it a configurable option, as there are other configurations (eg, label then image, label then image on next row, etc) and fewer config options is better.

[pyko]

Oh nice! Didn't know you can do that.

Bit obscure/hard to find, but definitely more flexible.

Agree that fewer config options are better.