It’s a full house in Belfast’s The Empire Music Hall for button accordionist Sharon Shannon – one of the standout concerts of this year’s Ulster Bank Belfast International Arts Festival. Only the week before in Chicago the Clare musician received the iBAM! (Irish Books Arts & Music) award for her outstanding contribution to music – a merited accolade for a musician who has carved out a highly successful international career on an instrument whose usual habitat is the pub session. Shannon follows a long line of notable Irish accordionists from Joe Burke and Joe Cooley to Tony MacMahon and Seamus…