see also issue #19.

practical examples:

• https://proxy.example.com:8080/;

  port 8080 is commonly used but 8080 is not a privileged port.

• running multiple services on the same host

  • https://www.example.com:443/ - already used for regular website
  • https://www.example.com:8080/ - another service (e.g. proxy, jenkins, any app really...)

• SSL endpoint not being apache/nginx but the app

  • uwsgi
  • tomcat / jetty / winstone servlet