[ticket/11716] Convert Soft Delete Mod to post/topic visibility

PHPBB3-11716
[ticket/11716] Rename migration files and add note that it's converting a MOD

PHPBB3-11716
[ticket/12176] Add functional test for founder deletion message.

PHPBB3-12176
[ticket/12176] Display correct message when trying to delete founder.

PHPBB3-12176
[ticket/12244] Rename link to Extensions Manager in the ACP

PHPBB3-12244
[ticket/12261] Remove web root path from login redirect url

The redirect url must be relative to the ucp.php and not relative to the
current page.

PHPBB3-12261
[ticket/12261] Add a functional test for redirect after using login_box()

PHPBB3-12261
[ticket/12261] Validate the redirect hidden field before submitting the form

PHPBB3-12261
[ticket/12261] Fix doc block

PHPBB3-12261
[ticket/12261] Mark test as incomplete, something is wrong with sessions

PHPBB3-12261
[ticket/12244] Rename extensions manager tab

PHPBB3-12244
[ticket/11716] Fix dependencies in migration files

PHPBB3-11716
[ticket/11716] Correct license URL

PHPBB3-11716
Merge remote-tracking branch 'EXreaction/ticket/11716' into develop

* EXreaction/ticket/11716:
  [ticket/11716] Correct license URL
  [ticket/11716] Fix dependencies in migration files
  [ticket/11716] Rename migration files and add note that it's converting a MOD
  [ticket/11716] Convert Soft Delete Mod to post/topic visibility
[ticket/12176] Add newest_user_colour to config array to ensure it exists

PHPBB3-12176
Merge remote-tracking branch 'vsephpbb/ticket/12244' into develop

* vsephpbb/ticket/12244:
  [ticket/12244] Rename extensions manager tab
  [ticket/12244] Rename link to Extensions Manager in the ACP
Merge pull request #6 from nickvergessen/ticket/bantu/12176

[ticket/12176] Add newest_user_colour to config array to ensure it exists

* nickvergessen/ticket/bantu/12176:
  [ticket/12176] Add newest_user_colour to config array to ensure it exists
Merge pull request #2104 from nickvergessen/ticket/12261

[ticket/12261] Remove web root path from login redirect url
[ticket/12176] Reword comment about config entries.

PHPBB3-12176
Merge remote-tracking branch 'bantu/ticket/12176' into develop-olympus

* bantu/ticket/12176:
  [ticket/12176] Reword comment about config entries.
  [ticket/12176] Add newest_user_colour to config array to ensure it exists
  [ticket/12176] Display correct message when trying to delete founder.
  [ticket/12176] Add functional test for founder deletion message.