feature #947 Adding Lithuania translation (uikolas)

This PR was squashed before being merged into the master branch (closes #947).

Discussion
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Adding Lithuania translation

Interesting that nobody have added Lithuania translation of demo application. In Lithuania Symfony is very popular and maybe for new users will be useful to see Lithuania translation.

Commits
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9020a0b Adding Lithuania translation

Author: javiereguiluz

config/services.yaml

@@ -3,7 +3,7 @@
 parameters:
     locale: 'en'
     # This parameter defines the codes of the locales (languages) enabled in the application
-    app_locales: en|fr|de|es|cs|nl|ru|uk|ro|pt_BR|pl|it|ja|id|ca|sl|hr|zh_CN|bg|tr
+    app_locales: en|fr|de|es|cs|nl|ru|uk|ro|pt_BR|pl|it|ja|id|ca|sl|hr|zh_CN|bg|tr|lt
     app.notifications.email_sender: [email protected]
 
 services: