Tutorial code

[kickoke]

This branch contains the tutorial content that we initially wanted to publish during the Google season of Docs project.
We've decided to make some alterations, for example, to include OGC examples instead of ISO examples.
The exercise descriptons for the lessons are stored in the file exercises.adoc. The file contains a liquid "case" structure to iterate through the different exercises.

The code for the exercises lives in the metanorma tutorial repository.
Since we don't have a playground directly on the website, I've told the users to download the repository and follow along in the files.

Before we merge, there are still some "Bugs" that I would like to address. I hope that @strogonoff might know how we can fix them.

• Review the Terms and definitions sections. Can you (@ronaldtse) check if the information is still fine or if we should introduce the Concepts and Designations, too? Does the absolute beginner need to know these?
• Tutorial needs to show up as a tab in the main navigation. I tried that in a local build but it broke the code. @strogonoff you might know how to amend this.
• The following lessons are a top-level navigation item: lesson-1, lesson-2, lesson-3, lesson-4. Because I used the base-docs.html template, they contain the automatically generated "further in this section" portion. I don't think this section is useful in the context of tutorials, so we need to touch the open-theme repository for this. However, because this is the theme repository for other sites too, we could probably create a new formatting template for the tutorials.
• @strogonoff If possible, I would like to change the appearance of some additional elements.
  

1. The task checkboxes should not have leading bullet points
2. The "Hint" dropdown is currently black, but to increase the awareness for them, I'd like them to be in one of our brand colors.
3. The button in each lesson is currently displayed as a link, although I have changed the respective Sass file. @strogonoff maybe you can have a look at this?

I hope we can solve these issues quickly so that users can finally benefit from the tutorial :)

[hound]

Declaration should be terminated by a semicolon
Selector should have depth of applicability no greater than 2, but was 3

[ronaldtse]

@kwkwan can you please help check these files and fix any problematic content? Also need to fix links. Thanks!

[ronaldtse]

Merging this and cleaning up later!