Add security layer to send file output things (#8189)

* Add security layer to send file output things

* Make telegram secure

* fix lint

* fix handling

* invert check

* resolve relative paths

* add test for relative paths

* fix lint

* fix tests

* Address paulus comments

* fix style

* fix tests

* Add more tests

* fix tests

* fix tests

* fix test p2

* fix lint

* fix tests

* Make it available for windows

* Change name / address comments

* fix set

* fix test

* fix tests

* fix test

* fix lint

tests/components/test_websocket_api.py

@@ -278,6 +278,9 @@ def test_get_config(hass, websocket_client):
 
     if 'components' in msg['result']:
         msg['result']['components'] = set(msg['result']['components'])
+    if 'whitelist_external_dirs' in msg['result']:
+        msg['result']['whitelist_external_dirs'] = \
+            set(msg['result']['whitelist_external_dirs'])
 
     assert msg['result'] == hass.config.as_dict()