A ‘BRITISH’ gunman who is believed to have filmed himself slaughtering Muslims in a New Zealand mosque wrote a chilling manifesto before the “terrorist attack”. The white-supremacist shooter, 28, who was born in Australia, said he wanted to take revenge for the "thousands of European lives lost to terror attacks". He boasted that he chose to use firearms so he could influence politics in the US. “Finally, to create conflict between the two ideologies within the United States on the ownership of firearms in order to further the social, cultural, political and racial divide within the United states," he wrote....