Adds docker and woodpecker files

.woodpecker.yaml

@@ -0,0 +1,15 @@
+when:
+  branch: main
+  event:
+    - push
+    - manual
+steps:
+  - name: build
+    image: woodpeckerci/plugin-docker-buildx
+    settings:
+      repo: git.halfbinary.net/${CI_REPO_OWNER}/scavengerhunt-api
+      registry: git.halfbinary.net
+      tags: ${CI_PIPELINE_NUMBER}
+      username: ${CI_REPO_OWNER}
+      password:
+        from_secret: docker_password