Merge infra and k3 into one directory again

Since I don't have multiple terraform steps anymore it simply doesn't
make sense to me anymore to split all tasks into separate folders.
Instead I try to be as clear as possible in the README to make it easy
to follow the structure in the future without too much headache.

site.yml

@@ -0,0 +1,34 @@
+- hosts: server
+  gather_facts: no
+  roles:
+  - role: server-setup
+    tags:
+    - init
+    - add-server
+- hosts: agent
+  roles:
+  - role: agent-setup
+    tags:
+    - init
+    - add-agent
+- import_playbook: k3s.orchestration.site
+  tags:
+  - init
+  - add-server
+  - add-agent
+- import_playbook: k3s.orchestration.upgrade
+  tags:
+  - update
+- hosts: server[0]
+  roles:
+  - role: kube-config
+    tags:
+    - init
+    - config
+    - update
+- hosts: localhost
+  roles:
+  - role: k8s-setup
+    tags:
+    - init
+    - k8s