* Always prefer port from forwarded host header (#103)

* Update changelog and README (#103)

* update mix packages to latest (minor updates only) (#177)

To view the diffs in each available update, visit:
https://hex.pm/l/kmMV8

* Resolve deprecation notice and Credo issue

Included as part of #177

Cowboy will automatically default to port 80 when no port has been
given, but Bandit does not. Bandit will always default to the
underlying port, which makes it hard to know if there was a port
specified or if a port was assumed.

This change ignores cowboy or bandit's assumption around port number
and parses it from the header directly.