Add python2 version (for certain plugins)

.drone.yml

@@ -11,3 +11,17 @@ steps:
     password:
       from_secret: docker_password
     repo: r.sbruder.de/calibre
+  depends_on: clone
+
+- name: docker-v2
+  image: plugins/docker
+  settings:
+    registry: r.sbruder.de
+    username:
+      from_secret: docker_username
+    password:
+      from_secret: docker_password
+    dockerfile: Dockerfile.python2
+    repo: r.sbruder.de/calibre
+    tags: python2
+  depends_on: clone

Dockerfile.python2

@@ -0,0 +1,7 @@
+FROM debian:buster
+
+RUN apt-get update \
+    && apt-get -y install --no-install-recommends calibre \
+    && rm -rf /var/lib/apt/lists/*
+
+ENTRYPOINT ["calibredb"]