With airlines cutting back, one area that has been curtailed severely is airline food. What used to be a freebie is now unavailable, or if it is available, it is often expensive and unappealing. Also, with more flights having interim stops, travel times have become longer and it may be a stretch before you can get a full meal. For those of you who travel by train, Amtrak occasionally has a food car, but, again, the selection is limited. So, for those of you looking to stay fortified while you travel, here are eight ideas for snacks to bring with you.