$ brew update
$ brew upgrade rbenv ruby-build
$ CONFIGURE_OPTS="--with-openssl-dir=`brew --prefix openssl` --with-readline-dir=`brew --prefix readline`" rbenv install 2.1.2
$ rbenv global 2.1.2
$ gem install bundler rbenv-rehash$ brew update
$ brew upgrade rbenv ruby-build
$ CONFIGURE_OPTS="--with-openssl-dir=`brew --prefix openssl` --with-readline-dir=`brew --prefix readline`" rbenv install 2.1.2
$ rbenv global 2.1.2
$ gem install bundler rbenv-rehash