Buffy the Vampire Slayer turns 20 today, and it still remains one of the most important and influential shows ever created. When Buffy debuted March 10, 1997 on The WB, it helped the merely two-year old network solidify its audience. While, yes, The WB used Buffy to primarily target teens—along with other mainstays like Dawson’s Creek and Felicity—the show quickly showed what it was capable of,…