Articles should have header images

[DeadSuperHero]

Shouldn't be that hard to add support for. This just basically requires a quick migration and some CarrierWave assignment. Would be really nice to make some kind of AJAXy button for a smooth upload of image.

As a bonus, that image can be passed as the og:image value for any article post.

[DeadSuperHero]

Probably going to work on this next, since the OpenGraph tag will need to pick up the header image by default.

Some tweaks to think about:

• Uploading needs to be AJAXy, in the sense that it visually updates on the client side before it is actually saved on the server.
• That might require a really specific kind of jquery plugin
• Eventually, this may all need to be refactored anyway.