CLEVELAND, OH (AP).- There’s always been room at the Rock and Roll Hall of Fame and Museum for the exciting, most popular relics, like Michael Jackson’s “Thriller” jacket and John Lennon’s Sgt. Pepper uniform. But most of the not-so-flashy mementos were tucked away in storage. Visitors will get a chance to see those hidden artifacts beginning later this year, when the museum opens its library and archives in a recently completed high-tech building it shares with Cuyahoga Community College’s creative arts programs. The museum has begun moving photos, recordings, albums and covers, oral histories, scrap books and other packed materials from its iconic glass pyramid overlooking Lake Erie to the new, low-key building two miles away. The items also include such gems as Jim Morrison’s first poem, video from the 1981-82 Rolling Stones tour and personal letters from the Grateful