Module versions

[Simon Peyton-Jones]

| In either case, the actual layout in filespace can be handled
| with symbolic links, e.g.
| 
|     Graphics/UI/Gtk.hs		-- symbolic link to Gtk_1_2.hs
|     Graphics/UI/Gtk_1_2.hs	-- the real module
| 
| At the moment, nhc98 will flag a warning (for instance) that
| 
|     module Gtk is called Gtk_1_2 in its interface file
| 
| but this is harmless.  I don't know how GHC currently copes
| with this kind of module/filename conflict?

GHC also complains if the filename and module name differ.
Except for Main.

Simon