While The Bee Gees have never truly faded from the popular consciousness, it’s fair to say the group founded by Barry Gibb and his late brothers Maurice and Robin is currently experiencing a renaissance.  Director Frank Marshall’s documentary How Can You Mend a Broken Heart earned acclaim for its candid chronicle of the group’s ups and downs while Barry has reaffirmed his legacy with the new album Greenfields: The Gibb Brothers Songbook Vol. 1.  On the latter, he’s joined by an array of country artists to reinvent the Bee Gees’ venerable songbook. …