[ticket/13277] Force IE to not cache AJAX requests.

Caching causes problems, such as the inability to move a forum/CPF/module in the
same direction by more than one row.

PHPBB3-13277
Merge pull request #3152 from prototech/ticket/13277

[ticket/13277] Force IE to not cache AJAX requests.
Merge branch 'develop-ascraeus' into develop