Expose that cookies insert order is kept

Author: slandelle

client/src/main/java/org/asynchttpclient/Request.java

@@ -23,7 +23,6 @@
 import java.net.InetAddress;
 import java.nio.ByteBuffer;
 import java.nio.charset.Charset;
-import java.util.Collection;
 import java.util.List;
 
 import org.asynchttpclient.channel.ChannelPoolPartitioning;
@@ -74,11 +73,11 @@ public interface Request {
     HttpHeaders getHeaders();
 
     /**
-     * Return Coookie.
+     * Return cookies.
      *
      * @return an unmodifiable Collection of Cookies
      */
-    Collection<Cookie> getCookies();
+    List<Cookie> getCookies();
 
     /**
      * Return the current request's body as a byte array