Portuguese translation (#4874)

* Create message.po

* Add files via upload

* Update config.py

* Update config.py

* portuguese translation - messages.json

po2json

* Update message.po

* Add files via upload

* Add files via upload

superset/config.py

@@ -165,6 +165,7 @@ LANGUAGES = {
     'zh': {'flag': 'cn', 'name': 'Chinese'},
     'ja': {'flag': 'jp', 'name': 'Japanese'},
     'de': {'flag': 'de', 'name': 'German'},
+    'pt': {'flag': 'pt', 'name': 'Portuguese'},
     'pt_BR': {'flag': 'br', 'name': 'Brazilian Portuguese'},
     'ru': {'flag': 'ru', 'name': 'Russian'},
 }