Fixing MetaRails

Two of the examples in my MetaRails talk (given yesterday) are already out of date. Rick Olson pointed out that the "around advice" idiom has already been DRYed out a bit, and David told me that reloadable classes had been totally reworked.

I don't have time to update the slides today though -- for next 72 hours I am completely buried preparing and teaching a Java course. Don't feel sorry for me though, I get to talk about the cool parts.