The initial lineup has been revealed for next year’s M3 Rock Festival. The event will take place at the Merriweather Post Pavilion in Columbia, Maryland on May 6-8 and it will feature the following: May 6: Kix, Lizzy Borden, Doro, and Count’s 77 (VIP only event). May 7: Tom Keifer, Extreme, Blue Öyster Cult, Stephen…