toolkit: update toolkit's Package types

Signed-off-by: Hank Donnay <hdonnay@redhat.com>
Change-Id: Icbab38c7f062c8d4e057bd8ca89ab1c26a6a6964

Author: hdonnay

toolkit/types/generate_string.go

@@ -2,12 +2,36 @@ package types
 
 import "bytes"
 
+// PackageKind indicates what kind of package is being described.
 type PackageKind uint
 
 const (
+	// "Unknown" is the default value.
 	UnknownPackage PackageKind = iota // unknown
-	SourcePackage                     // source
-	BinaryPackage                     // binary
+	// A "source" package is software that must be compiled or otherwise
+	// processed before it's ready to use.
+	//
+	// Conceptually, all "binary" packages come from a "source" package. A
+	// single "source" package produces one or more other packages.
+	//
+	// It can be used to describe the set of packages produced from the source
+	// package.
+	SourcePackage // source
+	// A "binary" package is compiled or otherwise ready-to-use software.
+	//
+	// It describes a set of files inside a container image.
+	BinaryPackage // binary
+	// A "layer" package is used to refer to a container layer itself.
+	//
+	// Conceptually, a "layer" package is a higher type that describes the
+	// container image rather than the contents.
+	LayerPackage // layer
+	// An "ancestry" package is used to refer to a container layer and all
+	// previous layers in an image.
+	//
+	// Conceptually, an "ancestry" package is a higher type that describes the
+	// container image rather than the contents.
+	AncestryPackage // ancestry
 )
 
 func (k PackageKind) MarshalText() (text []byte, err error) {