Add header, initial description, and some examples of supported regexes #394

	name: Build in-code documentation
	on: [push]
	jobs:
	build-and-deploy:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	with:
	repository: giellalt/giellalt.github.io

	- name: Install realpath
	run: \|
	which realpath

	# Mermaid processing starts here:
	- name: get list of files
	id: getfile
	run: \|
	echo "::set-output name=files::$(grep -rli --include=\*.md '^```mermaid' . \| xargs)"

	- name: print list of files for debugging
	run: \|
	echo ${{ steps.getfile.outputs.files }}

	- name: print working dir
	run: \|
	pwd

	- name: print working dir content
	run: \|
	ls -la

	# The actual Mermaid compilation
	- name: compile mermaid
	uses: divvun/compile-mermaid-markdown-action@main
	with:
	files: ${{ steps.getfile.outputs.files }}
	output: 'mermaid-svgs'
	env:
	HIDE_CODEBLOCKS: 1
	# The next one must be declared, with an empty value, for paths to work for us:
	ABSOLUTE_IMAGE_LINKS:
	OUTPUT_FILE_TYPE: "svg"


	- name: list generated svg fils
	run: \|
	ls -l mermaid-svgs

	- name: show changes
	run: \|
	git status

	# Mermaid processing ends here

	- name: deploy gh pages
	uses: peaceiris/actions-gh-pages@v3
	with:
	github_token: ${{ secrets.GITHUB_TOKEN }}
	publish_dir: .
	enable_jekyll: true

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