@WorkerThread
    public static boolean available() {
      // this is only one of many ways this can be done
      CommandResult result = run(Shell.AVAILABLE_TEST_COMMANDS);
      return Shell.parseAvailableResult(result.stdout, true);
    }
Detects whether or not superuser access is available, by checking the output of the "id"
command if available, checking if a shell runs at all otherwise

@return {@code true} if superuser access is available
imitate/src/main/java/com/engineer/imitate/shell/Shell.java