Gets a leaderboard by name, it will create it if it's not yet created. Leaderboards created with this function will not automatically show up in the Steam Community. You must manually set the Community Name field in the App Admin panel of the Steamworks website. As such it's generally recommended to prefer creating the leaderboards in the App Admin panel on the Steamworks website and using FindLeaderboard unless you're expected to have a large amount of dynamically created leaderboards.