Fix AskSage to work with the accepted_tos option, and to print any error

With sagecell.sagemath.org, the user will now have to specify `accepted_tos=>true`, which indicates their agreement to the server's terms of service.

So a valid call now is: `$sageReply1 = AskSage($SageCode1,{seed=>$problemSeed, accepted_tos=>true});`