Implement EZP-22568: Add Apache configuration & use for travis tests

Adds offical Apache configuration which is reused for testing
infrastructure as well, so avoiding duplicating vhost config across
online documentation and test infrastructure.
Remove PHP settings deprecated in 5.3 and removed in 5.4
[Travis] Warm up caches for behat env to avoid sahi timeouts
[Travis] Disable xdebug to speed things up
Merge pull request #145 from ezsystems/ezp-22568-apache_configuration

EZP-22568: Add Apache configuration & use for travis tests