If you want to use this package as your default system ruby, as root
create symbolic links like so (overwriting any previous default):
 ln -sf ${PREFIX}/bin/ruby24 ${PREFIX}/bin/ruby
 ln -sf ${PREFIX}/bin/erb24 ${PREFIX}/bin/erb
 ln -sf ${PREFIX}/bin/irb24 ${PREFIX}/bin/irb
 ln -sf ${PREFIX}/bin/rdoc24 ${PREFIX}/bin/rdoc
 ln -sf ${PREFIX}/bin/ri24 ${PREFIX}/bin/ri
 ln -sf ${PREFIX}/bin/rake24 ${PREFIX}/bin/rake
 ln -sf ${PREFIX}/bin/gem24 ${PREFIX}/bin/gem
