- Change the variable to always-headers so it can be extended in the future
- New function build-headers that assists combining complex logic headers
together with less mess
- Also apply headers to the proxy
http-easy connections are pooled, and streaming responses does not
automatically close the response (they are closed automatically in
other situations). After 128 (the default) opened connections to fetch
images, the pool ran out of connections, and future attempts would
just time out waiting for a connection.
Fixed by manually closing the connection at the correct time.