Update - fix for Server Error 500

Only real courses should be able to use this tool.  Need to check the course instance id for numeric and "ci:" prefix numerics.  If the course instance id is non-numeric and doesn't contain the prefix of "ci:", then the user will be given a message that the course is not properly configured with a valid course record.  
Are we guaranteed that the format of course IDs will never change (even when the new SIS system comes online)?