Improve Sky Hub error handling (#5762)

* Added error handling in function _get_skyhub_data

* Error line split for readability

homeassistant/components/device_tracker/sky_hub.py

@@ -111,6 +111,9 @@ def _get_skyhub_data(url):
 def _parse_skyhub_response(data_str):
     """Parse the Sky Hub data format."""
     pattmatch = re.search('attach_dev = \'(.*)\'', data_str)
+    if pattmatch is None:
+        raise IOError('Error: Impossible to fetch data from' +
+                      ' Sky Hub. Try to reboot the rooter.')
     patt = pattmatch.group(1)
 
     dev = [patt1.split(',') for patt1 in patt.split('<lf>')]