(Hook & Ladder Theater, 3010 Minnehaha Av. Davina & the Vagabonds, the Belfast Cowboys and International Reggae All-Stars are all set to perform on subsequent weekends in May. The series continues with piano legend Cornbread Harris' 95 th birthday bash featuring a special guest (7 p.m., Fri., $15-$20) and then two by rap-rocker Heatbox (5 and 7:30 p.m., $15-$20). Under the Canopy kickoff: Conceived and warmly received as a safe, diverse, community-oriented outdoor music option last year, the Hook & Ladder's Under the Canopy series returns with a bigger capacity and more room to dance starting with a KFAI-produced Cinco de Mayo celebration featuring Javier Trejo's new group Caballo Cósmico (7 p.m.