update configuration.sh for installing rbenv
update configuration.sh for installing rbenv

DaikiMaekawa/myenv-setup,DaikiMaekawa/env_setup,DaikiMaekawa/myenv-setup,DaikiMaekawa/daiki-env-setup,DaikiMaekawa/env_setup,DaikiMaekawa/daiki-env-setup,DaikiMaekawa/env_setup,DaikiMaekawa/daiki-env-setup