A few changes:
* 0-arity type specs like the following previously would not have the
expected 'variable.parameter' highlighting for the return type:
-spec foo() -> Value when Value :: term().
* Highlight module, type and function docs as documentation comments
and inject markdown into them.
* Replace `#match?` predicates with `#any-of?` where possible.
* Remove custom auto-pairs. Now that Erlang uses markdown for
documentation, the asciidoc-style backtick-singlequote pair is no
longer useful.
This doesn't work robustly (within pattern matches). Only regular
bindings are highlighted as parameters. In order to highlight all
parameters even in matches, we would need an arbitrary nesting operator
in queries which doesn't exist yet in tree-sitter.
