Refine thumbnails

[allanday]

The current thumbnails show the full content of the post, including formatting and additional headings. This can result in rather messy thumbnails which don't always help to identify posts.

For example, in this screenshot, you see lots of big "Link" text or secondary headings:

For the mockups, I followed the following rules for the thumbnails:

• Show the first image in the post that is sufficiently wide.
• If there isn't a suitable image, show text.
• Only show block text, and strip links/formatting.
• Crop images vertically if they won't fit.
• Only show text if there is room.
• Bottom align images.

If you follow those rules, you get something like this:

[ignatenkobrain]

@mcatanzaro would be great to have some help from you ;)