[release-notes] Start adding developer content

[Matthias Clasen <matthiasc src gnome org>]

commit 574685b01a71a8627dd43c355c0d89ee627845d6
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Sep 2 17:33:04 2020 -0400

    Start adding developer content

 help/C/developers.page | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
---
diff --git a/help/C/developers.page b/help/C/developers.page
index f5699958..71cfc688 100644
--- a/help/C/developers.page
+++ b/help/C/developers.page
@@ -32,6 +32,29 @@
     <p></p>
   </section>
 
+  <section>
+    <title>libhandy</title>
+    <p>libhandy is a library providing high-quality GTK widgets with a
+    focus on adaptive and mobile-friendly user interfaces. The version that
+    is included in GNOME 3.38, libhandy 0.80, brings many new widgets, such
+    as HdyDeck and HdyWindow.</p>
+    <p>libhandy is gearing up for a 1.0 release that will be parallel-installable
+    with the earlier 0.x versions.</p>
+  </section>
+
+  <section>
+    <title>Tracker</title>
+    <p>Tracker has a new <link href="https://gnome.pages.gitlab.gnome.org/tracker/";>website</link>
+    and greatly improved documentation. With version 3.0, tracker has moved from a
+    centralized to distributed database model. App developers are encouraged to
+    store data in app-local Tracker databases.</p>
+    <p>The file system indexed managed by Tracker Miner FS is now read-only.</p>
+    <p>Tracker's SPARQL core now fully supports SPARQL 1.1 query language,
+    including the SERVICE {} statement, which allows one database to query
+    from another.</p>
+    <p>The tracker3 commandline tool has also seen many improvements.</p>
+  </section>
+
   <section id="more">
     <title>Other Improvements</title>
     <p>Other improvements in GNOME &gnomeversion; include:</p>