Full Editor tutorial

[undavide]

Description

Add a tutorial for the Full Editor, alongside a new code sample

The page belongs to the guides/tutorials/ folder—same as the Getting Started tutorial of PR #162. A tutorial landing page has to be created, with links to them, but we can work & approve this PR in the meantime.

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] I have signed the Adobe Open Source CLA.
• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [ ] All new and existing tests passed.