MDL-45111 quiz responses report : fatal error when counting responses

not all possible responses where returned by question type method.
Merge pull request #25 from jamiepratt/MDL-45111-master

MDL-45111 quiz responses report : fatal error when counting responses
Update version.php for the 1.5 release.
Merge branch 'master' of https://github.com/moodleou/moodle-qtype_ddimageortext