Integrating editline with ghc

[Christian Maeder]

Judah Jacobson wrote:
> - System.Console.Editline.Readline contains the readline APIs provided
> by the editline library (mostly a cut/paste of
> System.Console.Readline).

I would like to see a restructuring of the old readline
package:

1. a _new_ readline package that only contains the interface that can be
implemented using libeditline _or_ libreadline. If this package is call
"readline" (with a new version number) most libraries i.e. like Shellac
would not need modifications.

2. Two further packages for extension of editline and those functions of
readline that are not part of "1". Maybe call these packages
editline-ext and readline-ext

The extended packages "2" could go under extra libs or hackageDB, while
   "1" remains a boot package for ghc that can link to editline on macs
and readline under linux, but has the same interface and package name!

Cheers Christian