add drone config file

.drone.yml

@@ -0,0 +1,25 @@
+# 345678911234567892123456789312345678941234567895123456789612345678971234567898
+kind: pipeline
+name: test-build
+
+versions:
+  - &ruby_container
+    ruby@sha256:7c77d7351acbf335aeda71bce3ef60403ce703de87064b885f340592e97cc11f
+
+steps:
+  - name: build
+    image: *ruby_container
+    commands:
+      - >
+          apt update
+          &&
+          apt install -yqq
+          bsdmainutils
+          ghostscript
+          imagemagick
+          nodejs
+          npm
+          time
+      - npm install -g yarn
+      - gem install bundler
+      - time make build