They may have once been a metal band, but you never would have known it when Weilheim, Germany’s the Notwist stopped at the 9:30 Club on Wednesday night, in support of their latest long player, the excellent The Devil, You + Me. Nearly 20 years into their career, the band seems to have settled into a more mature, introspective groove, largely trading in guitar-based indie-pop with pronounced electronic underpinnings. While the band managed to pack…