Fixed bug #457: SQL syntax error when having changed a question type from a question with activated 'other' option to a question type with no 'other' option and then activating the survey.

git-svn-id: file:///Users/Shitiz/Downloads/lssvn/source/phpsurveyor@1670 b72ed6b6-b9f8-46b5-92b4-906544132732