#608: broctl print times out if the table is too big

I think irrespective of the existence of the policy (and the variable),
timeout and not printing the vaule of a variable is still an issue which
needs to be addressed.

Also, for bro-2.0-beta released code, I tried printing a few variables

~bro/bro-20/bin/broctl print Scan::scan_triples

       bro Scan::scan_triples = <unknown id>

and saw the <unknown id> error.

Possible, I am missing something..?