added proxmox backup client docker image

pbsclient/dev/.gitignore

@@ -0,0 +1 @@
+pbsclient/dev/compose.override.yml

pbsclient/dev/compose.yml

@@ -0,0 +1,11 @@
+name: pbsclient-dev
+services:
+  app:
+    build:
+      dockerfile: docker/Dockerfile
+      context: ../
+    environment:
+      - APP_ENV=${APP_ENV}
+      - PBS_PASSWORD=${PBS_PASSWORD}
+      - PBS_REPOSITORY=${PBS_REPOSITORY}
+      - PBS_FINGERPRINT=${PBS_FINGERPRINT}