Wrong host port when only X-Forwarded-Proto is present

[pderop]

Motivation:
When resolving forwarded headers (X-Forwarded/Forwarded), the following scenario seems to happen in cloud foundry:

• you send an https request to a cloud foundry application, for example an actuator request: https://cloudfoundryapplication/actuator
• the front-end proxy forwards the request to a springboot application on non secure http 8080
• The request contains a Host header without any port, as well as a X-Forwarded-Proto: https header
• in this case, the DefaultHttpForwardedHeaderHandler class will wrongly resolve the host port as 80 instead of 443, because the request is received on a non-secure connection.
• And the json response then contains an unexpected 80 port appended in the actuator urls:

{"_links":{"self":{"href":"https://cloudfoundryapplication:80/actuator","templated":false},"health-path":{"href":"https://cloudfoundryapplication:80/actuator/health/{*path}","templated":true},"health": ...

Have also applied the similar patch for Forwarded headers (like Forwarded: proto=https).
Fixes #2771

[pderop]

in previous commit, drastically simplified the logic of the patch, based on Violeta's suggestions given privately (thanks !)

[pderop]

@violetagg , thanks for the review.