add ci pipeline

.drone.yml

@@ -0,0 +1,31 @@
+---
+kind: pipeline
+type: docker
+name: default
+
+steps:
+
+- name: docker
+  image: plugins/docker
+  settings:
+    repo: bunix42/pre-commit
+    username:
+      from_secret: docker_username
+    password:
+      from_secret: docker_password
+    tags:
+      - latest
+
+- name: slack
+  image: plugins/slack
+  settings:
+    webhook:
+      from_secret: slack_webhook
+    channel: drone
+    username: drone
+
+trigger:
+  branch:
+    - master
+  event:
+    - push