Greed quick mid-week update

I just put a new version of Greed out.

The main thing in this release is that Greed clears the WebView's cache when you're done reading a feed item. This keeps Greed's size down to around 760K, whereas before it was showing up as large as 7MB!

Also in this update:

• Mark all items as read within a folder (not just in a feed).
• Mark all items in all feeds as read.
• Mark all items in all labels as read.
• Fix crash when selecting "mark all as read" in the article list, then immediately exiting.
• Update notification: Next time there's a new version of Greed available, you'll be notified.