Merge branch '180-third-party' into 'develop'

Resolve "Add a documentation section to list related project"

Closes #180

See merge request funkwhale/funkwhale!164

changes/changelog.d/180.doc

+Added a documentation area for third-party projects (#180)

docs/index.rst

@@ -17,6 +17,7 @@ Funkwhale is a self-hosted, modern free and open-source music server, heavily in
    importing-music
    federation
    upgrading
+   third-party
    changelog
 
 Indices and tables

docs/third-party.rst

+Third party projects
+====================
+
+This page lists all known projects that are maintained by third-parties
+and integrate or relates to Funkwhale.
+
+.. note::
+
+    If you want your project to be added or removed from this page,
+    please open an issue on our issue tracker.
+
+
+API Clients
+-----------
+
+- `libfunkwhale <https://github.com/BaptisteGelez/libfunkwhale>`_: a Funkwhale API written in Vala
+- `Funkwhale-javalib <https://github.com/PhieF/FunkWhale-javalib>`_: a Funkwhale API client written in Java