[ŧicket/11896] Set form_time with time() when marking all notifications read

form_time is only set if is passed via the form. Since the mark notifications
read link does not use the form, it will default to 0 causing the mark
notifications logic to only mark notifications read if their time is smaller
or equal to 0. This patch will change ucp_notifications to correctly set
form_time for the confirm_box.

PHPBB3-11896
[ticket/11896] Add ability to define expected message after posting

This change will add the ability to define the expected message after a
topic or post has been submitted with the methods create_post() and
create_topic(). If the expected message is not 'POST_STORED', we will not
try to get the topic and post id.

PHPBB3-11896
[ticket/11896] Add functional tests for marking all notifications read

PHPBB3-11896
[ticket/12017] Remove IN_PHPBB defined check

PHPBB3-12017
[ticket/12017] Copy config/ dir so events work

PHPBB3-12017
[ticket/12017] Fix phpbb requirement in composer.json

PHPBB3-12017
Merge pull request #1872 from nickvergessen/ticket/12017

Ticket/12017 Extension tests are broken on current develop
[ticket/12008] The read_notification_last_gc config setting should be dynamic.

PHPBB3-12008
[ticket/12008] Update the run time value for the prune notifications cron task

PHPBB3-12008
Merge remote-tracking branch 'prototech/ticket/12008' into develop

* prototech/ticket/12008:
  [ticket/12008] Update the run time value for the prune notifications cron task
  [ticket/12008] The read_notification_last_gc config setting should be dynamic.
[ticket/11896] Minor code improvements in phpbb_functional_test_case

Use assertContainsLang() and get rid of unnecessary logic in create_post()
and create_topic(). The docblocks were also slightly improved.

PHPBB3-11896
[ticket/11896] Correctly document return of null in docblocks

Also got rid of previous incorrect comment in docblocks.

PHPBB3-11896
[ticket/12018] Use path_helper for admin style CSS in sql report

The path to the admin style CSS is currently created with $phpbb_admin_path.
We should however use the path_helper to correctly link to this file in order
to have a correct link on pages like extensions

PHPBB3-12018
Merge remote-tracking branch 'Marc/ticket/12018' into develop

* Marc/ticket/12018:
  [ticket/12018] Use path_helper for admin style CSS in sql report
[ticket/11896] Use $form_time and fix out of bounds $form_time

PHPBB3-11896
[ticket/12023] Add test for failing .css copy

PHPBB3-12023
[ticket/12023] Correctly compare the size of the array in ignore_new_files

PHPBB3-12023
Merge pull request #1877 from nickvergessen/ticket/12023

Ticket/12023 New css files missing after update
Merge remote-tracking branch 'Marc/ticket/11896' into develop

* Marc/ticket/11896:
  [ticket/11896] Use $form_time and fix out of bounds $form_time
  [ticket/11896] Correctly document return of null in docblocks
  [ticket/11896] Minor code improvements in phpbb_functional_test_case
  [ticket/11896] Add functional tests for marking all notifications read
  [ticket/11896] Add ability to define expected message after posting
  [ŧicket/11896] Set form_time with time() when marking all notifications read
[prep-release-3.1.0-a2] Update version to 3.1.0-a2