Add role documentation

README.adoc

@@ -0,0 +1,21 @@
+[[qois-infrastructure]]
+qo.is Infrastructure
+--------------------
+
+This repository contains the infrastructure configuration.
+
+Structure
+~~~~~~~~~
+
+`hardware`:: Hardware specific configuration files, e.g. for wireless
+cards.
+`host`:: Main nixos `configuration.nix` for every host. The
+`configuration.nix` is symlinked to the specific host file.
+`role`:: Host roles, which are included from a host's configuration.
+`docs`:: Documentation of the concrete qo.is infrastructure
+
+Development
+~~~~~~~~~~~
+
+* The nix files shoud be formatted using nixfmt:
+** `nixfmt -c $(git ls-files *.nix)`