Other: Updated translations. [skip ci]

Author: Reinmar

lang/translations/ar.po

@@ -1,4 +1,15 @@
 # Copyright (c) 2003-2019, CKSource - Frederico Knabben. All rights reserved.
+#
+#                                     !!! IMPORTANT !!!
+#
+#         Before you edit this file, please keep in mind that contributing to the project
+#                translations is possible ONLY via the Transifex online service.
+#
+#         To submit your translations, visit https://www.transifex.com/ckeditor/ckeditor5.
+#
+#                   To learn more, check out the official contributor's guide:
+#     https://ckeditor.com/docs/ckeditor5/latest/framework/guides/contributing/contributing.html
+#
 msgid ""
 msgstr ""
 "Language-Team: Arabic (https://www.transifex.com/ckeditor/teams/11143/ar/)\n"

lang/translations/ast.po

@@ -1,4 +1,15 @@
 # Copyright (c) 2003-2019, CKSource - Frederico Knabben. All rights reserved.
+#
+#                                     !!! IMPORTANT !!!
+#
+#         Before you edit this file, please keep in mind that contributing to the project
+#                translations is possible ONLY via the Transifex online service.
+#
+#         To submit your translations, visit https://www.transifex.com/ckeditor/ckeditor5.
+#
+#                   To learn more, check out the official contributor's guide:
+#     https://ckeditor.com/docs/ckeditor5/latest/framework/guides/contributing/contributing.html
+#
 msgid ""
 msgstr ""
 "Language-Team: Asturian (https://www.transifex.com/ckeditor/teams/11143/ast/)\n"