Invader ZIM: Enter the Florpus arrives on Netflix today with the aim of conquering the Earth at long last! It's been 13 years, almost to the day, since Jhonen Vasquez's Nicktoon was last on the air. However, the title alien menace had a tough time getting any regular airings on Nickelodeon and its affiliate networks. And fellow Nicktoon Hey Arnold! and its movie treatment didn't quite get the numbers that the parent network was looking for. Enter Netflix. The streaming giant recently released the Nickelodeon-backed special Rocko's Modern Life: Static Cling, and just one week …