[WIP] Validate hooks existence

Triple <code>`</code> is only required for [fenced code blocks](https://help.github.com/articles/github-flavored-markdown#fenced-code-blocks) - which, by the way, is a GitHub extension to Markdown. For regular code insertions within text a single <code>`</code> is enough.

```
Create a `.git_hooks.yml` on project root.
```