Rename "container" to "image"

- Updated `wwctl upgrade` to handle updates
- Maintained `.Container` and `.ContainerName` in tstruct
- Added `ContainerName()` methods to node and profile objects
- Added `--container`, `-C` aliases to wwctl commands (`<node|profile> <add|set>`)
- Added `wwctl container` alias
- Added support for `container_exit.sh` if `image_exit.sh` is not found

Signed-off-by: Jonathon Anderson <janderson@ciq.com>

internal/app/wwctl/image/exec/child/non-Linux.go

@@ -0,0 +1,15 @@
+//go:build !linux
+// +build !linux
+
+package child
+
+import (
+	"github.com/spf13/cobra"
+	"github.com/warewulf/warewulf/internal/pkg/wwlog"
+)
+
+func CobraRunE(cmd *cobra.Command, args []string) error {
+	wwlog.Error("This command does not work on non-Linux hosts")
+
+	return nil
+}