Bump version to 0.3.0
Bump version to 0.3.0

marshall-lee/nio4r,marshall-lee/nio4r,tpetchel/nio4r,celluloid/nio4r,tpetchel/nio4r,celluloid/nio4r,marshall-lee/nio4r,celluloid/nio4r,frsyuki/nio4r,frsyuki/nio4r,frsyuki/nio4r,tpetchel/nio4r