Add .drone.yml file for CI

.drone.yml

@@ -0,0 +1,26 @@
+kind: pipeline
+name: default
+
+steps:
+- name: docs
+  image: elixir:latest
+  commands:
+  - mix local.rebar --force
+  - mix local.hex --force
+  - mix deps.get
+  - mix docs
+	when:
+		event:
+			- push
+
+- name: publish
+  image: appleboy/drone-scp
+  settings:
+    user:
+      from_secret: ssh_username
+    password:
+      from_secret: ssh_password
+    host: haigure.net
+    target: /srv/http/haigure/www/aife
+    source: doc/*
+    strip_components: 1