 //  Copyright © 2016 Edmunds.com, Inc. All rights reserved.
 /**
     Encodes an outbound NSMutableURLRequest with security credentials
-    so that it can be authenticated on the receiving server.
+    so that it can be authenticated on the receiving server using HMAC
+    authentication.
+
+    After initializing and configuring an instance of NSMutableURLRequest,
+    encodeRequest adds the necessary HTTP request headers and signature
+    for HMAC authenticatation.
+
+    If you need to change the names of the query parameter and headers used
+    by HMAC, you can do so after initialization by setting:
+    -apiKeyQueryParameter
+    -signatureHTTPHeader
+    -timestampHTTPHeader
+    -versionHTTPHeader
 */
 
 import Foundation

    
    // MARK: - Utility Methods
    
    func getCurrentTimeStamp() -> String {
        let dateFormatter = NSDateFormatter()
        

    // MARK: - Main Method
    
    /**
     Encodes an outbound NSMutableURLRequest.
     Any query parameter string should be added to the URL before calling this method,
     and it should NOT contain the API key as it is added here.
     
