Fixed I Love Ruby broken link

Hello People,

Have fixed some broken links for . I hosted I Love Ruby book on Open Mail Box, but now since they have made their service paid, I have moved to github 100%.

Hope you find my book useful.

Great read, thanks for publishing this!

Thanks to Ruby and Free Software community, I am earning my bread for many years now. I have to do something so that people can learn for free and can possibly start to earn.