[ticket/12448] Allow null as default value for columns

PHPBB3-12448
[ticket/12448] Fix null columns for postgres

PHPBB3-12448
[ticket/12448] Fix null columns for MS SQL

PHPBB3-12448
[ticket/12861] Add event to modify the post, poster and attachment data

PHPBB3-12861
[ticket/12656] Pass user object into all console commands.

PHPBB3-12656
[ticket/12871] Add PHPBB_DISPLAY_LOAD_TIME const to config.php on installation

To make it consistent with another config.php constants,
PHPBB_DISPLAY_LOAD_TIME is to be put in config.php during installation as well.

PHPBB3-12871
[ticket/12560] Add methods to set upload and temp paths in plupload

The paths will be reset to the default paths after an upload is complete.

PHPBB3-12560
Merge pull request #2651 from nickvergessen/ticket/12448

[ticket/12448] Allow null as default value for columns
Merge pull request #2752 from bantu/ticket/12656

[ticket/12656] Pass user object into all console commands for translation
Merge pull request #2745 from nickvergessen/ticket/12861

[ticket/12861] Add event to modify the post, poster and attachment data

* nickvergessen/ticket/12861:
  [ticket/12861] Add event to modify the post, poster and attachment data
Merge pull request #2757 from rxu/ticket/12871

[ticket/12871] Add PHPBB_DISPLAY_LOAD_TIME const to config.php on installation

* rxu/ticket/12871:
  [ticket/12871] Add PHPBB_DISPLAY_LOAD_TIME const to config.php on installation
Merge pull request #2766 from marc1706/ticket/12560

[ticket/12560] Add methods to set upload and temp paths in plupload