Removed explicit string values since they are implicitly set member's name.

Source/ParameterEncoding.swift

@@ -28,15 +28,7 @@ import Foundation
     See http://tools.ietf.org/html/rfc7231#section-4.3
 */
 public enum Method: String {
-    case OPTIONS = "OPTIONS"
-    case GET = "GET"
-    case HEAD = "HEAD"
-    case POST = "POST"
-    case PUT = "PUT"
-    case PATCH = "PATCH"
-    case DELETE = "DELETE"
-    case TRACE = "TRACE"
-    case CONNECT = "CONNECT"
+    case OPTIONS, GET, HEAD, POST, PUT, PATCH, DELETE, TRACE, CONNECT
 }
 
 // MARK: - ParameterEncoding