[super updateConstraints] goes at the *end*.
Fix copyright notice.
Fix ambiguous layout in tag/rating view.
Delete leftover mogenerator stuff.

NSManagedObject can generate primitive accessors. Using the attribute/relation
name structs never really caught on. The underscore-superclasses are needless
complication since we're not running mogenerator anymore.
Automatically delete data store on failed migration.

It's just a cache, so no harm done.
Store actual NSURLs in attributes that ostensibly store URLs.
Rename thread icon image URL attributes on AwfulThread.

Just didn't like the names.
Delete "is" prefix from AwfulThread's boolean attributes.
Suffix AwfulUser.customTitle attribute with "HTML".
Delete redundant prefixes on model attributes.

`threadRating` doesn't communicate any more than just `rating`.
Fix parsing tests.