When the cyberhackers of Anonymous set their wrath on Boston police in February, they managed to bring down the department’s main news and information website, bpdnews.com. They also brought out the muse in the Boston cops, who responded with a clever video poking fun at the attack. Anonymous bragged that the site had fallen “to the swift merciless vengeance of the hive.’’ But if the cyberattack demoralized Boston officers, they certainly didn’t show it.