ltlcross --reference

Tobias Meggendorfer wrote in a private email:

I'd like to be able to run ltlcross as a sort of "check against a reference implementation". More precisely, it would be nice to be able to designate one translator as "reference" implementation (--reference 'ltl2tgba -H -f %f'). This reference then is trusted to always produce the correct output and is not checked for errors. Furthermore, all other tools will only be checked against this reference, i.e., intersection checks (and potentially cross-comparison checks) will only be performed with the reference result instead of all other results.

Such an option would also need to be implemented in autcross for consistency.