Add Tutorials section

[michel-tricot]

What

• Add Tutorial section
• Change section ordering (connector before install)
• remove the jupyter notebook since there is nothing to guarantee that it will be up to date. @ChristopheDuong let me know if you think there is a way to keep it in sync with the md

@ChristopheDuong I think we should split the tutorial in 2:

1. config & log access
2. access to dbt models and how to use them

NOTE: I will do another change directly on master to remove the duplicated files

[johnlafleur]

Just wanted to fix Mac OS into macOS (which is the official name), and Gitbook changed all assets...

Apart from that, why not having "Tutorials" as the 2nd section (so just under Overview), and "Getting Started" as the 1st tutorial? If we have many tutorials we can categorize them into subsections but keep the most important ones as "Getting Started" out of those subsections and immediately visible.