It's useful for us to know, which version of which software is serving gems. This patch adds an `"X-Powered-By"` response header with the value of `"geminabox VERSION"`, e.g. `"geminabox 0.6.0"`. Example: geminabox$ bundle exec rackup $ curl -I localhost:9292 HTTP/1.1 200 OK ... X-Powered-By: geminabox 0.6.0
…cting it. At some point, when it's Hoe addiction has been solved, I'll just depend on multipart-post.