Create page for refname matching documentation
Antora 3.0 improved and added a lot of pattern matching capabilities for some of the playbook keys (e.g., tags, branches). The most explanatory info exists on Multiple Start Paths, but there are snippets on Branches, Worktrees, Fallback Version, and Version Key.
We want to provide an overview of the matching syntax that applies to these keys in a page called "Refname matching". The page would have the following outline:
- Value types (single value or array)
- Exact match/literal
- Basic glob/primitive
- Inclusions followed by exclusions
- Braces for ranges and items
- Repeats