Make KucoinAuth public

Author: Fernando Fernandes

Sources/SwiftTrader/Model/Kucoin/KucoinAuthentication.swift renamed to Sources/SwiftTrader/Model/Kucoin/KucoinAuth.swift

@@ -1,6 +1,6 @@
 //
-//  KucoinAuthentication.swift
-//  
+//  KucoinAuth.swift
+//
 //
 //  Created by Fernando Fernandes on 29.01.22.
 //
@@ -9,7 +9,18 @@ import Foundation
 
 /// Holds data required to authenticate the requests against Kucoin APIs.
 public struct KucoinAuth {
+
+    // MARK: - Properties
+
     public let apiKey: String
     public let apiSecret: String
     public let apiPassphrase: String
+
+    // MARK: - Lifecycle
+
+    public init(apiKey: String, apiSecret: String, apiPassphrase: String) {
+        self.apiKey = apiKey
+        self.apiSecret = apiSecret
+        self.apiPassphrase = apiPassphrase
+    }
 }