docs: improve swagger

- use markdown files in swagger
- automate version, use swager.conf template
- embed swagger ui index.html as docs.html

.gitignore

@@ -70,4 +70,7 @@ usr/bin/aptly
 dpkgs/
 debian/changelog.dpkg-bak
 
-docs/
+docs/docs.go
+docs/swagger.json
+docs/swagger.yaml
+docs/swagger.conf