You can now create custom hook templates for code blocks, either one for all (`render-codeblock.html`) or for a given code language (e.g. `render-codeblock-go.html`).
We also used this new hook to add support for diagrams in Hugo:
* Goat (Go ASCII Tool) is built-in and enabled by default; just create a fenced code block with the language `goat` and start draw your Ascii diagrams.
* Another popular alternative for diagrams in Markdown, Mermaid (supported by GitHub), can also be implemented with a simple template. See the Hugo documentation for more information.
Updates #7765Closes#9538Fixes#9553Fixes#8520Fixes#6702Fixes#9558
E.g.:
```
> foo
> bar
{.myclass}
```
There are some current limitations: For tables you can currently only apply it to the full table, and for lists the ul/ol-nodes only, e.g.:
```
* Fruit
* Apple
* Orange
* Banana
{.fruits}
* Dairy
* Milk
* Cheese
{.dairies}
{.list}
```
Fixes#7548
