fix(id3): fix panic on SplitAttribute being nil
fix(id3): fix panic on SplitAttribute being nil

thedadams/golearn,thedadams/golearn,EtienneBruines/golearn,sjwhitworth/golearn,sjwhitworth/golearn,sjwhitworth/golearn,sjwhitworth/golearn,thedadams/golearn,EtienneBruines/golearn,thedadams/golearn,sjwhitworth/golearn,EtienneBruines/golearn