Update Swift code for Xcode 6 beta 5

Mostly mundane tweaks for changes to Swift. The two big ones are that swift's
name mangling is now just "module.classname" and that all properties have to be
explicitly declared as `dynamic`.

Closes #733.
I don't think writing the tests should be any more difficult - we should still be able to get the className using the class method ```className``` from our tests classes, and this should return the right namespace based on the test target.