Added error handling for unknown operators

lib/SugarTrail/Template/Condition.pm

     my $want    = $params->{$name}; # what they want
 
     # execute the right handler
-    return &{ $self->{handlers}->{$op} }($want, $have);
+    if (exists $self->{handlers}->{$op}) {
+        return &{ $self->{handlers}->{$op} }($want, $have);
+    } else {
+        helper::dmupp(bad_op=>$self);
+        warn "unknown operator: $op\n";
+    }
 }