Jem Aswad Senior Music EditorIn the five years since his death from cancer in January 2016, David Bowie’s estate has kept fans captivated with an extensive, tastefully curated series of reissues that have presented a vast amount of material in a non-overwhelming manner. Happily, that same approach is evident in the “Bowie 75” pop-up stores (so named for his 75th birthday in January of next year), which opened in London and New York on Monday.