Fix the script to not wantonly drop availability annotations, and
update NSCocoError accordingly. Also drop in a reinterpret-casting
rawValue initializer, which matches what we get when importing enums
from C.
Swift SVN r28563
Bridging the Cocoa error domain requires us to gather constants from
Foundation, CoreData, and AppKit, then pulling those into a single
(_)NSCocoaError enum that conforms to
_ObjectiveCBridgeableErrorType.
Rather than using a table extracted from the appropriate Cocoa headers
and pushing that through gyb, just hardcode the resuting Swift code,
which is produced (manually) by an enumeration-parsing script. Thanks
to Dave for pointing out that I was holding gyb wrong.
... and apologies for the Perl.
Long term, we need a better solution here, but this will suffice for
the short term.
Swift SVN r28560
