Changes to tutorial

[robbiejackson]

Hi, is the repository code still being maintained here? I made some changes on the tutorial pages to step 12 (Adding Categories) and a little fix to step 11 (Verifications), and was wondering if you were wanting to include them here.

I see that there are branches down to step 10 only here, but there are more on the scionescire repo, so I'm wondering if this repository is still in use.