darcs patch: Split known-extensions off into their ow... (and 3 more)

4 patches for repository http://darcs.haskell.org/packages/Cabal: Tue Oct 26 00:26:24 BST 2010 Ian Lynagh * Split known-extensions off into their own type, and remove knownExtensions The knownExtensions list had already got out of sync with the datatype. Now we use an Enum instance to get the list of constructors. Also, having the actual extensions in a separate type than UnknownExtension and EnableExtension makes it easier to add extension disabling support later. Tue Oct 26 14:11:21 BST 2010 Ian Lynagh * Generalise deprecatedExtensions It now works with Extensions rather than KnownExtensions Tue Oct 26 14:12:50 BST 2010 Ian Lynagh * Tweak a couple of types Tue Oct 26 15:55:03 BST 2010 Ian Lynagh * Add support for general extension en/disabling