Refactor Package structure

This commit cleans up the package structure, to make two new top-level
packages `internal` (for internal-use packages) and `pkg` (for general
shared utility code).

internal/component/ssh/ssh.go

@@ -0,0 +1,25 @@
+package ssh
+
+import (
+	"embed"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/component"
+)
+
+type SSH struct {
+	component.ComponentBase
+}
+
+func (SSH) Name() string {
+	return "ssh"
+}
+
+//go:embed all:stack
+var resources embed.FS
+
+func (ssh SSH) Stack() component.Installable {
+	return ssh.ComponentBase.MakeStack(component.Installable{
+		Resources:   resources,
+		ContextPath: "stack",
+	})
+}