added internet connection testing

Author: keflavich

astroquery/tests/test_internet.py

@@ -0,0 +1,9 @@
+# Licensed under a 3-clause BSD style license - see LICENSE.rst
+from astropy.tests.helper import remote_data
+import requests
+
+@remote_data
+def test_net_connection():
+    R = requests.post('http://httpbin.org/post', 
+                      headers={'User-Agent':'astropy:astroquery.0.1.dev'})
+    R.raise_for_status()