refactor(cli): move cmd/uncloud to cmd/uc, change the artifact name uncloud_* -> uc_*

cmd/uc/image/root.go

@@ -0,0 +1,19 @@
+package image
+
+import (
+	"github.com/spf13/cobra"
+)
+
+func NewRootCommand() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "image",
+		Short: "Manage images on machines in the cluster.",
+	}
+
+	cmd.AddCommand(
+		NewListCommand(),
+		NewPushCommand(),
+	)
+
+	return cmd
+}