[libxmlplusplus] NEWS: Note the move to GitHub

[Murray Cumming <murrayc src gnome org>]

commit 604ae3c286a20683f9688f8da5221b3bf89886d0
Author: Murray Cumming <murrayc murrayc com>
Date:   Sun Jan 5 17:32:39 2020 +0100

    NEWS: Note the move to GitHub
    
    See https://github.com/libxmlplusplus/libxmlplusplus

 NEWS | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/NEWS b/NEWS
index b640e30..9f8aac0 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,6 @@
+This code has moved to:
+https://github.com/libxmlplusplus/libxmlplusplus
+
 3.0.1 (stable):
 
 * Element::remove_attribute(): Delete the C++ wrapper