[gimp-web/testing] Add link in /docs/ to docs.gimp.org page for old versions

[Pat David <patdavid src gnome org>]

commit 18709e6bf5e75112ccbefcf83351fca7dc509e29
Author: Pat David <patdavid gmail com>
Date:   Wed Sep 12 09:39:48 2018 -0500

    Add link in /docs/ to docs.gimp.org page for old versions

 content/docs/index.md | 4 ++++
 1 file changed, 4 insertions(+)
---
diff --git a/content/docs/index.md b/content/docs/index.md
index 1eb56b6b..7c291e55 100644
--- a/content/docs/index.md
+++ b/content/docs/index.md
@@ -27,6 +27,10 @@ The user manual for the GIMP 2.10 release is available in 17 languages:
 *   [Slovenščina](http://docs.gimp.org/2.10/sl)
 *   [Svenska](http://docs.gimp.org/2.10/sv)
 
+The user manuals for older releases can be found at the [GIMP Documentation page][].
+
+[GIMP Documentation page]: https://docs.gimp.org/download.html "The GIMP Documentation"
+
 ## Tutorials
 
 [Tutorials on gimp.org](/tutorials/)