git-imap-send.txt: add note about localized Gmail folders

The name of the "Special-Use Mailboxes" in Gmail are localized
using the user's localization settings. Add a note to that effect
in `git imap-send`'s documentation, to make it easier for users to
configure their account.

Signed-off-by: Philippe Blain <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: phil-blain

Documentation/git-imap-send.txt

@@ -110,6 +110,10 @@ Using Gmail's IMAP interface:
 You might need to instead use: `folder = "[Google Mail]/Drafts"` if you get an error
 that the "Folder doesn't exist".
 
+[NOTE]
+If your Gmail account is set to another language than English, the name of the "Drafts"
+folder will be localized.
+
 Once the commits are ready to be sent, run the following command:
 
   $ git format-patch --cover-letter -M --stdout origin/master | git imap-send