Prefer square brackets for %i and %w

These return lists, and so square brackets emphasize that a list is
returned.

Change-Id: I962658b6ed8519e6072d3231e936d71731d2b331
Reviewed-on: http://gerrit.causes.com/36434
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>