message: Fix incomplete command help text
diff: @@ -1378,7 +1378,7 @@ public:
  else
  std::cerr << " (This does not require admin permission)" << std::endl;
  std::cerr << std::endl;
  - std::cerr << " If you want to install system-wide, run 'vulkanlayer --system'."
  + std::cerr << " If you want to install system-wide, run 'vulkanlayer --register --system'."
  << std::endl;
  std::cerr << " (This requires admin permission)" << std::endl;
  