split: replace internal packages with images library

Remove all the internal package that are now in the
github.com/osbuild/images package and vendor it.

A new function in internal/blueprint/ converts from an osbuild-composer
blueprint to an images blueprint.  This is necessary for keeping the
blueprint implementation in both packages.  In the future, the images
package will change the blueprint (and most likely rename it) and it
will only be part of the osbuild-composer internals and interface.  The
Convert() function will be responsible for converting the blueprint into
the new configuration object.

vendor/github.com/osbuild/images/internal/workload/anaconda.go

@@ -0,0 +1,7 @@
+package workload
+
+// TODO: replace the Anaconda pipeline by the OS pipeline with the
+// anaconda workload.
+type Anaconda struct {
+	BaseWorkload
+}

vendor/github.com/osbuild/images/internal/workload/custom.go

@@ -0,0 +1,22 @@
+package workload
+
+type Custom struct {
+	BaseWorkload
+	Packages         []string
+	Services         []string
+	DisabledServices []string
+}
+
+func (p *Custom) GetPackages() []string {
+	return p.Packages
+}
+
+func (p *Custom) GetServices() []string {
+	return p.Services
+}
+
+// TODO: Does this belong here? What kind of workload requires
+// services to be disabled?
+func (p *Custom) GetDisabledServices() []string {
+	return p.DisabledServices
+}

vendor/github.com/osbuild/images/internal/workload/sap.go

@@ -0,0 +1,6 @@
+package workload
+
+// TODO!
+type SAP struct {
+	BaseWorkload
+}

vendor/github.com/osbuild/images/internal/workload/static_webserver.go

@@ -0,0 +1,7 @@
+package workload
+
+// TODO: replace the CommitServerTree pipeline by the OS pipeline with the
+// StaticWebserver workload.
+type StaticWebserver struct {
+	BaseWorkload
+}

vendor/github.com/osbuild/images/internal/workload/workload.go

@@ -0,0 +1,30 @@
+package workload
+
+import "github.com/osbuild/images/pkg/rpmmd"
+
+type Workload interface {
+	GetPackages() []string
+	GetRepos() []rpmmd.RepoConfig
+	GetServices() []string
+	GetDisabledServices() []string
+}
+
+type BaseWorkload struct {
+	Repos []rpmmd.RepoConfig
+}
+
+func (p BaseWorkload) GetPackages() []string {
+	return []string{}
+}
+
+func (p BaseWorkload) GetRepos() []rpmmd.RepoConfig {
+	return p.Repos
+}
+
+func (p BaseWorkload) GetServices() []string {
+	return []string{}
+}
+
+func (p BaseWorkload) GetDisabledServices() []string {
+	return []string{}
+}