[CGI] avoided undefined %*ENV<QUERY_STRING> fail
[CGI] avoided undefined %*ENV<QUERY_STRING> fail

It seems that in general, one cannot assume that a particular key in
%*ENV exists. Therefore, code should, as early as possible pull out
somthing like C<< %*ENV<SOME_KEY> // '' >> and then treat it uniformly
as a string.

viklund/november,viklund/november,viklund/november