Another seminal album of the mid-’00s indie rock boom is getting reissued this year: Bloc Party’s debut Silent Alarm. A 20th anniversary edition of the album, available on two CDs or four white vinyl LPs on September 26, will pair the original album (featuring favorites “She’s Hearing Voices,” “Helicopter,” “So Here We Are” and “Banquet”) with 23 B-sides and rarities, including nine unreleased demos and live cuts. An accompanying booklet will feature rare photos from the band’s personal collections as well as liner notes, including a foreword by the album’s co-producer Paul Epworth….