+: test-cors.org test

http://client.cors-api.appspot.com/client#?client_method=POST&client_credentials=true&server_url=http%3A%2F%2Fsejmometr.pl%2Fsejm_posiedzenia&server_enable=true&server_status=200&server_credentials=false&server_tabs=remote&client_headers=Accept%3A%20application%2Fvnd.EPF_API.v1%2Bjson