Specify netlify build

Addresses: #1135

	Follow https://www.starfallprojects.co.uk/posts/deploy-mkdocs-netlify/
	to eventually fix #1135.

	I realise this litters the main directory somewhat, but I hope
	that once the publication fully works and we turn the site into
	redirects, we can remove these files again. So only a temporary
	measure.

Signed-off-by: Daniel Holbach <daniel@weave.works>

.gitignore

@@ -19,3 +19,6 @@ dist/
 bin/
 output/
 cmd/flux/manifests/
+
+# Docs
+site/

netlify.toml

@@ -0,0 +1,3 @@
+[build]
+  command = "mkdocs build"
+  publish = "site"

requirements.txt

@@ -0,0 +1,2 @@
+mkdocs==1.1.2
+mkdocs-material==7.1.3

runtime.txt

@@ -0,0 +1 @@
+3.7