Is it springtime for Hitler in the 21st century?From eBooks, to Google Maps, to political polemics, to cafes, one of the biggest mass murderers in world history seems to be on many people’s minds. But one thing seems to elude their thoughts: the almost incomprehensible barbarity of one of history’s worst mass murders who snuffed out men, women, children and infants -- and who made his victims’ last minutes so obscenely terrifying.Suddenly, after being dead for 69 years, Adolf Hitler is a big author again. Earlier this month, it was reported that Amazon and iTunes had a new top-ranked book: Hitler’s 1925, 387-page anti-semitic manifesto “Mein Kampf,” in which he laid out many of his murderous plans.