Git merges in Moodle 1.9.19 by Dan Poltawski

commit e1d726afcf9263cfa4ed18c6b338a86bf8ec9445
Author: Dan Poltawski <dan@moodle.com>
Date:   Fri, 25 May 2012 16:38:31 +0800
Tag:    v1.9.19

Merge branch 'w21_MDL-28676_m19_mysqli' of git://github.com/skodak/moodle into MOODLE_19_STABLE