Fix Response.isRedirected, close AsyncHttpClient#391

Author: Stephane Landelle

api/src/main/java/org/asynchttpclient/providers/ResponseBase.java

@@ -80,7 +80,16 @@ public final FluentCaseInsensitiveStringsMap getHeaders() {
 
     @Override
     public final boolean isRedirected() {
-        return (status.getStatusCode() >= 300) && (status.getStatusCode() <= 399);
+        switch (status.getStatusCode()) {
+        case 301:
+        case 302:
+        case 303:
+        case 307:
+        case 308:
+            return true;
+        default:
+            return false;
+        }
     }
 
     @Override