#close not called on response body

[zbristow]

It looks like format_body is not calling close on the response body after iterating over it. I found this when trying to use Rack::CommonLogger with my app and not seeing the expected log entries show up in my CloudWatch logs. It turns out this middleware relies on body.close to be called to emit a log message.

Since this is part of the Rack spec to call close if the body responds to it, can format_body be updated to do this? I was able to get this middleware working after patching locally, so I can submit a PR with a fix if you'd like.

[logandk]

@zbristow Thanks for reporting, I'd appreciate a PR, since you already patched locally.