meta: add Drone CI support

.drone.yml

@@ -0,0 +1,20 @@
+---
+kind: pipeline
+
+steps:
+  - name: build
+    image: alpine
+    environment:
+      host:
+        from_secret: ssh_host
+      username:
+        from_secret: ssh_username
+      key:
+        from_secret: ssh_private_key
+      port: 22
+    commands:
+      - apk add -q openssh-client
+      - mkdir ~/.ssh
+      - echo "$key" > ~/.ssh/id_ed25519
+      - chmod 600 ~/.ssh/id_ed25519
+      - ssh -o StrictHostKeyChecking=no $username@$host ./build.sh