[gspell] readme: add notes for packagers

[Sébastien Wilmet <swilmet src gnome org>]

commit 0fd425236d757b821a731c36709244c9aa47e073
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Apr 21 14:43:27 2017 +0200

    readme: add notes for packagers
    
    https://bugzilla.gnome.org/show_bug.cgi?id=772406

 README |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)
---
diff --git a/README b/README
index 819f71c..3b39a4e 100644
--- a/README
+++ b/README
@@ -35,6 +35,18 @@ Dependencies
 * Enchant >= 1.6.0
 * iso-codes
 
+Notes for packagers
+-------------------
+
+At least on GNU/Linux, it is better to install hunspell. aspell can be
+considered deprecated and doesn't work well with gspell. If both hunspell and
+aspell are installed, Enchant prefers hunspell.
+
+See also:
+
+    https://fedoraproject.org/wiki/Releases/FeatureDictionary
+    https://wiki.ubuntu.com/ConsolidateSpellingLibs
+
 Installation from a tarball
 ---------------------------