Fix Request.php so HTTP_HOST will take precedence over SERVER_NAME

In nginx for example the SERVER_NAME is the first value which is configured after server_name

for example:
server_name server1.com server2.com serverN.com

SERVER_NAME in php env will be server1.com
While HTTP_HOST will be the requested URL
Update Request.php
Update Request.php
Update Request.php
Update RequestTest.php
Update RequestTest.php

Added test for spoofed HTTP_HOST
Update Request.php
Merge pull request #4581 from mbn18/master

Hostname route ignore HTTP_HOST and give SERVER_NAME precedence
[#4581] CS fixes, composer updates

- Import hostname validator
- CS around arguments for hostname validator constructor
- Added zend-validator to required components, as it's used for hostname
  validation
Merge branch 'hotfix/4581'

Close #4581