* Added descriptors for gtkspell and its support package pspell.
Gtkspell is an optional dependency of Pan, so we should add the
ability to nix-instantiate to instantiate variants of a package
based on a selection of features.
svn path=/nix/trunk/test/; revision=16
files) are now referenced using their cryptographic hashes.
This ensures that if two package descriptors have the same contents,
then they describe the same package. This property is not as
trivial as it sounds: generally import relations cause this property
not to hold w.r.t. temporality. But since imports also use hashes
to reference other packages, equality follows by induction.
svn path=/nix/trunk/pkg/; revision=5
