Add henna for analphobes

As I discussed in issue #273, this pull request allows the player to buy a henna from Yara in the piercing shop. Buying the henna also applies a perk, and players with that perk (and a vagina) have most anal sex scenes rewritten, usually to vaginal sex, or avoided entirely.

One significant issue with this patch is that I haven't done anything with the bee girl encounters. Bee girl butt pregnancies use the same number as minotaur vaginal pregnancies, so I can't easily rewrite the existing ovipositing scenes to vaginal, and there's no existing non-anal content to limit the user to. I could disable bee girl encounters entirely, but that would cut the user off from bee honey and pure honey, which are needed for a couple of different quests. If you don't think that's an issue in practice, I can probably implement that pretty easily.

There are some other potential issues—for instance, I wrote some new Yara content, which her original author might have something to say about. There's also a question of how much the henna should cost, particularly since some players don't exactly play CoC to *win*. And finally, there are some naming questions—in particular, the perk I'm applying is rather unimaginatively named. I'm willing to edit things if anyone has better ideas.

(P.S. You may want to look over my code changes—I've never written ActionScript before, and while it seems like a pretty simple language, I may have made a few mistakes. The perk refactoring landing in the middle of this didn't help either, although the new system is definitely much improved.)