make bytecode incompatibility message more helpful
make bytecode incompatibility message more helpful

tkob/parrot,FROGGS/parrot,gitster/parrot,gitster/parrot,gagern/parrot,youprofit/parrot,tkob/parrot,tkob/parrot,tkob/parrot,tkob/parrot,tkob/parrot,gagern/parrot,FROGGS/parrot,parrot/parrot,FROGGS/parrot,gitster/parrot,gagern/parrot,gagern/parrot,youprofit/parrot,gitster/parrot,youprofit/parrot,gitster/parrot,FROGGS/parrot,parrot/parrot,youprofit/parrot,FROGGS/parrot,gitster/parrot,parrot/parrot,youprofit/parrot,tkob/parrot,gagern/parrot,youprofit/parrot,youprofit/parrot,youprofit/parrot,tkob/parrot,FROGGS/parrot,parrot/parrot,gagern/parrot,parrot/parrot,FROGGS/parrot,gagern/parrot,gitster/parrot,FROGGS/parrot