2.4 installer and Ruby-Tk

[jamgard]

Does not install Ruby-Tk or give an option to do so

[larskanis]

tk was removed from ruby-2.4 stdlibs but is still available as a gem. Use:

ridk exec pacman -S mingw-w64-x86_64-tk
gem install tk

I just opened a pull request which will automatically issue the pacman command while gem install tk in the future.

[larskanis]

The tk gem auto-installs the tk-package now: ruby/tk#10 (comment)