Race "entity" strings cleanup

[zyx-xyzzy]

Fixes Chocolate Bunnies being set to use the regular vulpine entity string instead of their own, and adds new entity strings for the two alt-races that didn't have them previously (Holiday Elves and Turkey). Also, switched the placeholder entity setting for protoplasm over from being hardcoded text to being a localizable string like the real races have, for consistency's sake.