Added page for GNOME desktop integration

user_manual/pim/sync_gnome.rst

@@ -0,0 +1,39 @@
+====================================
+Synchronizing with the GNOME desktop
+====================================
+
+The `GNOME desktop <https://www.gnome.org>`_ has built-in support for Nextcloud's calendar,
+contacts and tasks which will be displayed by the Evolution PIM or the
+Calendar, Tasks and Contacts app as well has for files, which it
+integrates into the Nautilus file manager via WebDAV. The latter works
+only while the computer is connected. 
+
+This can be done by following these steps:
+
+1. In the GNOME settings, open Online Accounts 
+2. Under "add an account" pick ``Nextcloud``.
+
+.. image:: ../images/gnome-online-accounts.png
+
+3. Enter your server URL, username and password. If you have enabled two
+   factor authentification, you need to generate an
+   app-password/token, because GNOME doesn't support OAuth yet. (`Learn more <https://docs.nextcloud.com/server/stable/user_manual/session_management.html#managing-devices>`_).
+
+.. image:: ../images/goa-add-nextcloud-account.png
+   
+4. In the next window, select which resources GNOME should access and
+   press the cross in the top left to close.
+   
+.. image:: ../images/goa-nextcloud-select.png
+
+Nextcloud task, calendars and contacts should now be visibile in the
+Evolution PIM, the task, contacts and calendars app.
+
+Files will be shown as a WebDAV resource in the Nautilus file manager
+(and also be available in the GNOME file open/save
+dialogues). Documents should be integrated into the GNOME Documents
+app.
+
+All resourses should also be searchable from anywhere by pressing the Windows key and entering a
+search tearm. 
+