Slipknot mastermind Shawn "Clown" Crahan has created a cannabis line. Dubbed "Clown Cannabis," the line will officially be out on May 17. As of now, upon entering the website, visitors are asked to confirm that they are above the age of 21. A green cartoon of Clown's most notable, Slipknot-era mask appears over a black marijuana leaf pattern on the homepage, where you can scroll down to sign up for the brand's newsletter. You can…