Added redirect and modified api reference section

docs/source/reference/api/user.md

@@ -0,0 +1,34 @@
+# Users
+
+## Module: {mod}`jupyterhub.user`
+
+```{eval-rst}
+.. automodule:: jupyterhub.user
+```
+
+### {class}`UserDict`
+
+```{eval-rst}
+.. autoclass:: UserDict
+   :members:
+```
+
+### {class}`User`
+
+```{eval-rst}
+.. autoclass:: User
+   :members: escaped_name
+
+   .. attribute:: name
+
+      The user's name
+
+   .. attribute:: server
+
+      The user's Server data object if running, None otherwise.
+      Has ``ip``, ``port`` attributes.
+
+   .. attribute:: spawner
+
+      The user's :class:`~.Spawner` instance.
+```