Added command and list execution (#1), small touchups

- Added exec command to execute individual commands
- Added --lists, -l flag to backup command
  - Run command lists (#1)
- Small touchups and documentation

cmd/root.go

@@ -41,6 +41,7 @@ func init() {
 	rootCmd.PersistentFlags().BoolVarP(&verbose, "verbose", "v", false, "Sets verbose level")
 
 	rootCmd.AddCommand(backupCmd)
+	rootCmd.AddCommand(execCmd)
 }
 
 func initConfig() {