Document Mac variants

Signed-off-by: Michal Čihař <michal@cihar.com>

docs/user/translating.rst

@@ -81,9 +81,9 @@ While translating you can use following keyboard shortcuts:
     Navigates to previous translation in current search.
 :kbd:`Alt+PageDown`
     Navigates to next translation in current search.
-:kbd:`Alt+Enter` or :kbd:`Ctrl+Enter`
+:kbd:`Alt+Enter` or :kbd:`Ctrl+Enter` or :kbd:`Command+Enter`
     Saves current translation.
-:kbd:`Ctrl+Shift+Enter`
+:kbd:`Ctrl+Shift+Enter` or :kbd:`Command+Shift+Enter`
     Umarks translation as fuzzy and submits it.
 :kbd:`Alt+E`
     Focus translation editor.