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/pkg/image/build.go

@@ -0,0 +1,52 @@
+package image
+
+import (
+	"fmt"
+	"path"
+
+	"github.com/pkg/errors"
+
+	"github.com/warewulf/warewulf/internal/pkg/util"
+	"github.com/warewulf/warewulf/internal/pkg/wwlog"
+)
+
+func Build(name string, buildForce bool) error {
+	wwlog.Info("Building image: %s", name)
+
+	rootfsPath := RootFsDir(name)
+	imagePath := ImageFile(name)
+
+	if !ValidSource(name) {
+		return errors.Errorf("Image does not exist: %s", name)
+	}
+
+	if !buildForce {
+		wwlog.Debug("Checking if there have been any updates to the image source directory")
+		if util.PathIsNewer(rootfsPath, imagePath) {
+			wwlog.Info("Skipping (Image is current)")
+			return nil
+		}
+	}
+
+	ignore := []string{}
+	excludes_file := path.Join(rootfsPath, "./etc/warewulf/excludes")
+	if util.IsFile(excludes_file) {
+		var err error
+		ignore, err = util.ReadFile(excludes_file)
+		if err != nil {
+			return fmt.Errorf("Failed creating directory: %s: %w", imagePath, err)
+		}
+	}
+
+	err := util.BuildFsImage(
+		"Image "+name,
+		rootfsPath,
+		imagePath,
+		[]string{"*"},
+		ignore,
+		// ignore cross-device files
+		true,
+		"newc")
+
+	return err
+}