Endpoint [/api/meta]: improve response clarity

[aemino]

The current results of /api/meta are:

  "name": "Test Server",
  "description": "Description of Server",
  "api_version": 1,
  "players": 0,
  "max_players": 16,
  "games": 0,
  "max_games": 100
}

The fields players and games are not sufficiently explicit; they could mean either a numerical count or an array of objects. To resolve this confusion, they should be renamed to num_players and num_games, respectively.

  "name": "Test Server",
  "description": "Description of Server",
  "api_version": 1,
  "num_players": 0,
  "max_players": 16,
  "num_games": 0,
  "max_games": 100
}