Add Ruby Tutorial For Beginners (#3100)
* Add Ruby Tutorial For Beginners
Hi,
This adds a new free Ruby tutorial (HTML version), **optionally** visitors can download a PDF version of the book by entering an email address.
## What does this PR do?
Add Resource
### Description
Free Ruby tutorial / book for beginners in HTML format with multiple lessons, including installing Ruby, conditionals, loops & object-oriented programming.
### Why is this valuable
It's a complete Ruby tutorial for beginners that helps learn Ruby from scratch. Includes examples, clear explanations & exercises.
### How do we know it's really free?
I made it.
### For book lists, is it a book?
Yes.
### Checklist:
- [x] Not a duplicate
- [x] Included author(s) if appropriate
- [x] Lists are in alphabetical order
- [x] Needed indications added (PDF, access notes, under construction)
* Use Full Book Name
Jesus Castello