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

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

PHPBB3-12176
[ticket/12176] Add newest_user_colour to config array to ensure it exists

PHPBB3-12176
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
[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.