re-arrange the user docs (#76)

* re-arrange the user docs

* Minor description edit

* update styles

* fix service links

Co-authored-by: kn0wmad <kn0wmad@protonmail.com>
Co-authored-by: Lucy Cifferello <12953208+elvece@users.noreply.github.com>

site/source/user-manual/index.rst

@@ -0,0 +1,27 @@
+.. _user-manual:
+
+===========
+User Manual
+===========
+
+Welcome to the EmbassyOS user manual. Here you will discover all that you Embassy can do!
+
+.. toctree::
+  :includehidden:
+  :maxdepth: 2
+
+  initial-setup
+  connecting/index
+  dashboard-overview
+  customize
+  backups/index
+  managing-services/index
+  service-guides/index
+  sessions
+  wifi
+  ssh
+  alt-marketplaces
+  updating
+  forgot-password
+  device-guides/index
+  misc-guides/index