[gimp-web/testing] userfaq.md: link to the Selling page

[Alexandre Prokoudine <aprokoudine src gnome org>]

commit 3dad2574fa210d0656dc8d4c200c4d32428a9cd7
Author: Alexandre Prokoudine <alexandre prokoudine gmail com>
Date:   Wed Oct 3 12:31:36 2018 +0000

    userfaq.md: link to the Selling page

 content/docs/userfaq.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/content/docs/userfaq.md b/content/docs/userfaq.md
index 18cb88ab..b747cb75 100644
--- a/content/docs/userfaq.md
+++ b/content/docs/userfaq.md
@@ -38,7 +38,8 @@ your changes to the source code under GPLv3+ as well.
 
 Yes, under terms of the General Public License this is perfectly legal,
 provided that the seller also gave you the source code of GIMP and any
-modifications he/she introduced.
+modifications he/she introduced. Please see 
+[this page](https://www.gimp.org/about/selling.html) for more information.
 
 ### Are you trying to develop a Photoshop killer app?