docs: Initial docs structure and infrastructure

NOTE: sphinx-autodoc is NOT included, because the way it works is by
importing python modules, which are (apart from commands) not used in
this repository, therefore it doesn't work.

docs/Makefile

@@ -0,0 +1,21 @@
+SPHINXOPTS    =
+SPHINXBUILD   = sphinx-build
+SPHINXAUTOBUILD = sphinx-autobuild
+SPHINXPROJ    = Leapp repository
+SOURCEDIR     = source
+BUILDDIR      = build
+
+all: clean html
+
+help:
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+livehtml:
+	@$(SPHINXAUTOBUILD) --watch ../repos --watch ../commands "$(SOURCEDIR)" "$(BUILDDIR)/html" $(SPHINXOPTS) $(0)
+
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	echo $@
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+
+.PHONY: all help Makefile

docs/requirements-docs.txt

@@ -0,0 +1,7 @@
+sphinx==7.2.6
+sphinx_rtd_theme
+sphinxcontrib-jquery
+docutils
+CommonMark
+myst-parser
+sphinx-autobuild