Updated Linux fixes for Swift 3.1

Author: cipi1965

Sources/Just/Just.swift

@@ -100,12 +100,8 @@ public enum HTTPMethod: String {
 
 extension URLResponse {
   var HTTPHeaders: [String: String] {
-    #if os(Linux)
-    return (self as? HTTPURLResponse)?.allHeaderFields ?? [:]
-    #else
     return (self as? HTTPURLResponse)?.allHeaderFields as? [String: String]
       ?? [:]
-    #endif
   }
 }
 
@@ -202,13 +198,8 @@ public final class HTTPResult : NSObject {
   public lazy var cookies: [String: HTTPCookie] = {
     let foundCookies: [HTTPCookie]
     if let headers = self.response?.HTTPHeaders, let url = self.response?.url {
-      #if os(Linux)
-      foundCookies = HTTPCookie.cookies(withResponseHeaderFields: headers,
-                                        forURL: url) as [HTTPCookie]
-      #else
       foundCookies = HTTPCookie.cookies(withResponseHeaderFields: headers,
                                         for: url) as [HTTPCookie]
-      #endif
     } else {
       foundCookies = []
     }