[ticket/12983] Correctly validate sorting options in the UCP

PHPBB3-12983
[ticket/12983] Add functional test for ucp pref module

PHPBB3-12983
[ticket/13046] Call phpbb_load_extensions_autoloaders() in $download/file.php

PHPBB3-13046
[ticket/13047] Add $post_list array to core.viewtopic_modify_page_title event

PHPBB3-13047
[ticket/12983] Do not test invalid values until Symfony 2.4

PHPBB3-12983
Merge pull request #2925 from nickvergessen/ticket/12983

Ticket/12983 UCP preferences, Display posts ordering by: input is not properly validated
Merge pull request #2928 from Nicofuma/ticket/13046

[ticket/13046] Call phpbb_load_extensions_autoloaders() in $download/file.php

* Nicofuma/ticket/13046:
  [ticket/13046] Call phpbb_load_extensions_autoloaders() in $download/file.php
Merge pull request #2929 from rxu/ticket/13047

[ticket/13047] Add $post_list array to core.viewtopic_modify_page_title event

* rxu/ticket/13047:
  [ticket/13047] Add $post_list array to core.viewtopic_modify_page_title event