add information about antora

[kersten1]

What is Antora

Basic components of Antora

• Structure
• Playbook
• Angora.yml
• UI
• Index

Set up a specification for Antora

• New project
• New group in navigation?
• Adding a card
• Overview pages
• Numbering
• Configuring an old project

Building your content

• Testing locally
• Testing in angora-dev
• Building a PDF

Publishing your spec

• Under development
• Ratified Spec

- UI tips and tricks