[gedit] docs: roadmap-done: add more done tasks

[Sébastien Wilmet <swilmet src gnome org>]

commit a4e983cf227580c80a7d9736b0270033a9453a14
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sun Nov 22 07:49:26 2020 +0100

    docs: roadmap-done: add more done tasks

 docs/roadmap-done.md | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)
---
diff --git a/docs/roadmap-done.md b/docs/roadmap-done.md
index 92f57c6df..508129b54 100644
--- a/docs/roadmap-done.md
+++ b/docs/roadmap-done.md
@@ -4,7 +4,24 @@ gedit roadmap - done tasks
 Tepl-ification
 --------------
 
-- gedit 3.36: start to use the Tepl library.
+- gedit 3.36:
+       - Start to use the Tepl library.
+       - Use some Tepl utility functions.
+       - Use TeplFileMetadata, remove GeditMetadataManager.
+- gedit 3.38:
+       - Move some utility functions to the Tepl library.
+       - Refactor and move some I/O error infobars to Tepl.
+       - GeditView now inherits from TeplView.
+       - Port to the new Tepl metadata API.
+       - Use TeplStyleSchemeChooserWidget in the preferences dialog.
+       - Create GeditFactory class, subclass of TeplAbstractFactory.
+- gedit 40:
+       - Use `tepl_pango_font_description_to_css()`.
+       - Use TeplLanguageChooser's, for choosing a language for the syntax
+         highlighting.
+       - Use TeplProgressInfoBar.
+       - GeditDocument now inherits from TeplBuffer, start to use the
+         TeplBuffer and TeplFile APIs.
 
 Links:
 - https://wiki.gnome.org/Projects/Tepl
@@ -16,3 +33,10 @@ New version of gedit on Windows
 It was done during the GNOME 3.38 development cycle. The integration with
 Windows is not perfect, but it works. It is planned to improve gedit for
 Windows over time.
+
+Documentation for contributors
+------------------------------
+
+Write a guide to get started with gedit development.
+
+Done during the GNOME 3.34 development cycle.