Fixing validation errors on the feed

http://validator.w3.org/feed/check.cgi?url=http%3A%2F%2Frefinedbitspodcast.com%2Ffeed.xml

I went ahead and listed myself as managing editor and webmaster. I did so because it recommends having a real name, but we could also make it "Refined Bits" if you'd rather.

I put "yes" for the explicit value mainly because have guests and we don't want to censor them. I'm not sure if we've actually used any explicit language though.