Add unique_id to sensors

Makes them show up in the integrations and makes them
editable.

Fixes #3
Fixes #4

Author: foosel

custom_components/coronavirus_hessen/sensor.py

@@ -40,6 +40,10 @@ def available(self):
     def name(self):
         return self._name
 
+    @property
+    def unique_id(self):
+        return self._name
+    
     @property
     def icon(self):
         return "mdi:biohazard"