email: change default from name to Grafana

Changes default from name in smtp settings
from Grafana Admin to Grafana.

Fix for integration test (which is skipped but that
did not work)

docs/sources/http_api/admin.md

@@ -158,7 +158,7 @@ with Grafana admin permission.
         "cert_file":"",
         "enabled":"false",
         "from_address":"admin@grafana.localhost",
-        "from_name":"Grafana Admin",
+        "from_name":"Grafana",
         "host":"localhost:25",
         "key_file":"",
         "password":"************",

docs/sources/installation/configuration.md

@@ -543,7 +543,7 @@ Verify SSL for smtp server? defaults to `false`
 Address used when sending out emails, defaults to `admin@grafana.localhost`
 
 ### from_name
-Name to be used when sending out emails, defaults to `Grafana Admin`
+Name to be used when sending out emails, defaults to `Grafana`
 
 ## [log]