REST Update Settings API should not take timeout and master_timeout as index parameters

closes elastic#4692

Author: kimchy

src/main/java/org/elasticsearch/rest/action/admin/indices/settings/RestUpdateSettingsAction.java

@@ -78,7 +78,7 @@ public void handleRequest(final RestRequest request, final RestChannel channel)
             }
         }
         for (Map.Entry<String, String> entry : request.params().entrySet()) {
-            if (entry.getKey().equals("pretty")) {
+            if (entry.getKey().equals("pretty") || entry.getKey().equals("timeout") || entry.getKey().equals("master_timeout")) {
                 continue;
             }
             updateSettings.put(entry.getKey(), entry.getValue());