Try to fail silently on Soup attribute errors

I was getting errors like the following when trying to minify a few email templates within celery tasks (to avoid clipping by GMail). 

`AttributeError: 'NavigableString' object has no attribute 'name'`
`AttributeError: 'Comment' object has no attribute 'name'`

Tried to silence these errors by using `getattr`, so in the worst case, we're failing silently instead of blowing up.