Make pydeface work with multivolume anatomicals

[Shotgunosine]

I'm preparing a study that's got some despot sequences in it for release. The despot sequences are multivolume anatomicals that I'd like to deface, so I added a try except on the multiplication of the mask and input image.

[chrisgorgo]

Thanks.

Any reason why using try/except instead of an if?

[Shotgunosine]

Not a strong reason one way or the other. In this case I went with try/except instead of if because this case is likely to be rare and try/except avoids slowing down the code in the majority of cases in which its unnecessary.

[chrisgorgo]

Cool - thanks!