Update copyright-fixing script for Tests folder.
Add target for smiley custom keyboard extension.

* Also add a framework for common smiley keyboard code between the app and the extension.
* Coerce command-line test runner to work with smiley framework tests.
* Bump project-wide deployment target to iOS 8.0.
Start a Smiley data model.

The plan is to ship a read-only database of smileys with the app. A read-write database will hold metadata plus any newly-downloaded smileys. Since the metadata relationship is typically cross-store, we need to weakly relate it with a fetched property.