What one earth do you do after witnessing the brutal (and narratively ambiguous) murder of your own parents? Grow up to be a smoking hottie with revenge dripping off every exquisite sinew, that’s what. Zoe Saldana does her best in the deeply silly action-drama Colombiana, but as a film that’s never quite sure of its audience, the only things that ever really hit the mark are the bullets flying in every direction except hers…