[gspell] In case someone is looking for *Flatpak* and gspell

[Sébastien Wilmet <swilmet src gnome org>]

commit 70d977808f5692e6b3aee4a26021f56e29f92229
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Aug 16 10:07:41 2019 +0200

    In case someone is looking for *Flatpak* and gspell
    
    The notes are hidden in the docs/ directory, that directory is not only
    for the gtk-doc stuff.

 HACKING | 10 ++++++++++
 1 file changed, 10 insertions(+)
---
diff --git a/HACKING b/HACKING
index 883172b..c629088 100644
--- a/HACKING
+++ b/HACKING
@@ -8,3 +8,13 @@ gspell follows the same guidelines and code conventions as GtkSourceView:
 The gspell GitLab:
 
     https://gitlab.gnome.org/GNOME/gspell
+
+Development notes
+-----------------
+
+See the text files in the docs/ directory (if you're looking to integrate
+gspell with *Flatpak*, it's there ;-) ).
+
+There are also some notes on the wiki:
+
+    https://wiki.gnome.org/Projects/gspell